F.A.Q. (Frequently Asked Questions) This section lists some common questions about PKZIP and related subjects. We hope you will find this information helpful. PKZIP for DOS Q. How do I compress a single file? ================================== A. Compressing a single file is quite easy. Enter the directory where the file you wish to compress is located and type: pkzip filename.zip myfile.ext In the above example, filename.zip is the .ZIP file to be created and myfile.ext is the file to be compressed. Q. How do I uncompress a .ZIP file? ===================================== A. Uncompressing a single file is just as easy as compressing a single file. Enter the directory where the .ZIP file is located and type: pkunzip filename.zip Q. How do I zip up subdirectories? =================================== A. To zip up subdirectories, you must both recurse subdirectories and preserve path names. This is done with the -r and -P options in combination. The options may be placed together as -rP. An example: pkzip -rP backup.zip c:\dir\*.* When a .ZIP file is created with paths stored, these paths will be visible in a view of the file (-v). An example: pkzip -v backup.zip To re-create these subdirectories, or to place files into their original subdirectories, the -d option must be used with PKUNZIP. An example: pkunzip -d backup.zip Q. How can I compress my entire C drive using PKZIP? ===================================================== A. The command to compress you entire C drive would be: pkzip -& -rp a:\backup.zip c:\*.* The -& is the option that indicates you wish to span the .ZIP file to multiple diskettes. The -rp option indicates you wish to preserve the path structures. If you want to backup a drive other than your C drive, use: pkzip -& -rp: a:\backup.zip d:\*.* This would backup your entire D drive. You can substitute any drive letter for d: on the above command line. Q. Why do I get the message "Bad Command or Filename"? ======================================================= A. If you see this message, DOS is telling you it can't find the program to which you are referring. This can happen because you are either not spelling the name of the program properly, you didn't put a space between the program name and its options, or the program is not in your path. Please see the Installation section of your PKZIP for DOS manual, and your MS-DOS manual for more information. Q. How do I span floppy diskettes? =================================== A. To zip a single large file to multiple floppy diskettes, you should use the -& option. An example of this would be: pkzip -& a:\backup.zip c:\myfile.ext In the above example, A:\backup.zip is the .ZIP file to be created and C:\myfile.ext is the large file I wished to compress across the diskettes. Q. Why can't I span under Windows NT? ====================================== A. The "&" character is a command line terminator under Windows NT, so you will need to place it in quotations for it to accept the option properly. Use the following example: pkzip "-&" a:\backup.zip c:\myfile.ext Q. How do I unzip a single file that is in a subdirectory in the .ZIP file? ============================================================================ A. Type PKUNZIP with the name of the .ZIP file and the name of the particular file you want. Let's assume you have a file named test.ZIP file with these files in it: file1.txt apple\file2.txt apple\banana\file3.txt To extract only "file2.txt" from this .ZIP file, you must specify the complete name. This would include the path. pkunzip test.zip apple\file2.txt Note there is no leading slash. This is how PKUNZIP differentiates between the files you are extracting with paths, and the target directory. "file2.txt" would be extracted to the current directory. If you wanted to extract it with its subdirectory, simply include the -d option on the command line. Using the above test.ZIP file, we could extract the entire contents of the apple subdirectory easily: pkunzip -d test.zip apple\*.* If we did it as shown above we would not only extract all the files in the "apple" subdirectory, but also the "banana" subdirectory below it and any files it contains. To extract only the "apple" subdirectories contents, and nothing else, we must exclude those directories we do not wish to extract: pkunzip -d test.zip apple\*.* -xapple\banana\*.* If the "apple" subdirectory had multiple subdirectories off it, you would need to exclude each one individually on the command line. Q. I am receiving insufficient memory when using PKZIP for DOS. Why? ===================================================================== A. If you are receiving an insufficient memory message, most likely it is because you are trying to compress more files than you have available conventional memory. PKZIP for DOS requires approximately 200K of conventional memory to run, plus 100 bytes per file you attempt to add. Your options are to free up more conventional memory if possible or to compress less files. Using the above calculations, the DOS version can compress approximately 5000 files. Note: PKZIP for Windows can compress up to 16,000 files. Q. I am experiencing a problem with PKZIP and Novell 4.x. Is there a known problem? ===================================================================== A. We are aware of a problem with Novell 4.x and PKZIP for DOS. Please use a -~ option when compressing and it should correct the problem. Q. My PKUNZIP reports I need version 7.3 or 2.8 to extract the file. What is the cause? ====================================================================== A. A bad FTP transfer. When a .ZIP file is not transmitted as a BINARY file, it will corrupt and cause PKUNZIP to incorrectly identify the version number. 2.04G is the current version of PKUNZIP. Re-transmit the file as a BINARY file, and PKUNZIP 2.04G will extract the file properly. PKZIP for Windows Q. How do I create a .ZIP file with PKZIP for Windows? ======================================================= A. To create a .ZIP file: 1. At the PKZIP main application screen, click on File. 2. Click on New. 3. Type a name for your .ZIP file. PKZIP automatically appends the .ZIP extension for you. 4. When you have finished with this dialog box, click on Save. The Add Files dialog box appears. 5. Select the files you want to compress into your .ZIP file. 6. When you have finished selecting files, click on OK to start compressing. Q. How do I extract a file from a .ZIP or .EXE file? ===================================================== A. To extract files from a .ZIP or .EXE file: 1. In PKZIP for Windows, open the .ZIP or .EXE file from which you want to extract files. 2. From the menu bar, select Extract. The Extract menu appears. 3. Select Extract files. The Extract dialog box appears. 4. Select a destination for your files. 5. Click on Extract to start extracting. 6. Click on Done after the last file is extracted. Q. Can I span diskettes with PKZIP for Windows? ================================================ A. The current version of PKZIP for Windows (2.60) has the ability to create a multiple volume archive (spanned .ZIP file). When PKZIP for Windows fills the contents of a removable media, it will automatically prompt for another diskette. Q. Does the Windows version support AV? ========================================= A. The current version of PKZIP for Windows (2.60) can recognize an AV signature, but it can not create one. That is something that is under consideration for future Windows versions. Q. Does the Windows version support command line ability? ========================================================== A. Currently there is no command line ability for PKZIP for Windows. PKZIP Command Line for Windows 95/NT supports long file names. The two products are available together in a product bundle. Q. I have the registered version of PKZIP for Windows but the option to run a program after extraction is still grayed out. Why? ===================================================== A. The ability to run a program after extraction or enable the title bar are in the Professional Distribution Licensed version only. With PKZIP for Windows, there are three versions: Shareware, Registered and the Distribution Licensed. For information about obtaining the Professional Distribution Licensed version, please contact sales@pkware.com. Q. I am having a problem transferring a file from a WIN 95 machine to a WIN 3.1x machine. Why? =================================================================== A. It has come to PKWARE’s attention that there is a volume label incompatibility between Windows 95 and Windows 3.1x. You can resolve this problem by using freshly formatted diskettes. Q. I’m getting a general protection fault error when using PKZIP for Windows. What could be the reason? ====================================================================== A. If you are using a Microsoft IntelliMouse, you must disable the Smart Speed option. It is currently incompatible with PKZIP for Windows. Q. What is the difference between a WIN 16 SFX, WIN 32 SFX, PKSFX, and PKSFX-Jr Self-Extracting files? ===================================================================== A. There are four types of Self-Extracting files you can create with the Registered version of PKZIP 2.60 for Windows. The WIN 16 SFX file is a 16-bit Windows self-extractor that can be run under Windows 3.1x, WIN NT or WIN 95. The WIN 32 SFX file is a 32-bit Windows self-extractor that can be run under Windows 95 or NT. A PKSFX file is a DOS Self-Extracting file that is run from a DOS prompt on any DOS machine or in a DOS prompt under Windows. A PKSFX-Jr is a smaller version of the DOS Self-Extractor that does not have any of the features of the normal PKSFX file. It offers only one option: the -o to overwrite files. Q. What are PKTMP*.* files? ===================================================== A. When you open a file from within PKZIP for Windows by double-clicking on it in the main application window, selecting Extract | Open from the menu bar, or using the Open option on the right-click menu, PKZIP temporarily extracts the file (by default) into the directory where the .ZIP file resides so the associated application may open the file and display it. PKZIP names these temporary files with a prefix of PKTMP. If, for example, you opened a file named readme.txt (residing in a .ZIP file) from within PKZIP for Windows, the file would be extracted and temporarily saved with a name similar to PKTMP000.TXT and subsequently displayed in Windows Notepad. When you close the file and/or Windows Notepad, the temporary file should be automatically removed. However, there may be instances where PKZIP does not remove such files. These files will not harm anything and can be safely deleted via Windows Explorer or File Manager. Q. How do I make sure these PKTMP*.* files are deleted by PKZIP? ===================================================== A. The user may optionally specify the temporary extract directory in the Extract Preferences (click Extract | Preferences) dialog to more easily keep track of these temporary files. Users of the 32-bit version of PKZIP have another option, in such instances, of specifying a time out interval in the PKZIPW.INI to remove temporary files more quickly. The PKZIPW.INI file is typically located in the Windows directory (e.g. C:\WINDOWS). If necessary, use the Windows Find/Search utility to locate the PKZIPW.INI file. By default PKZIP for Windows waits 5000 milliseconds (5 seconds) after you close a temporary file (e.g. PKTMP000.TXT) before deleting the file. If you determine that PKZIP is not removing temporary files automatically, you may wish to decrease the amount of time before deletion to an interval less than 5000 milliseconds. To specify an interval of zero seconds (no delay) for temporary file removal, add the following entry to your PKZIPW.INI file: [LFN] RemoveTempAfter=0 This value can be modified to delay temporary file deletion from 0 to 60000 milliseconds (0 to 60 seconds). Decreasing this value to something less than 5000 milliseconds facilitates more efficient automatic temporary file deletion. Q. Why can't I open certain archive format (e.g. UUEncoded; XXEncoded; MIME; BinHex; Tar; GZIP) files in PKZIP for Windows? ===================================================== A. The archive file may be corrupt or contain information (or is missing information) in the body or header. As such, PKZIP is unable to understand the file format code and therefore unable to open the file. Typically, PKZIP for Windows will display the following message and/or error when it encounters a problem with an archive file: "Errors were found in the .ZIP file, attempt to fix" or "No CE signature found..." PKZIP displays the first message because it is unable to determine what type of file it is and assumes that it is a damaged .ZIP file. Unfortunately, the fix option will only repair files archived in the .ZIP format. It will not repair files archived in other formats. The second message is an error indicating that PKZIP is unable to determine the file type, .ZIP or otherwise. Verify that the file is not corrupt and that it is in a valid archive file format. If necessary, contact the file creator to determine how the file was created. If you determine that the file is indeed a valid archive, send a copy of the archive with information on how it was created to support@pkware.com. Q. How does PKZIP for Windows compare to WinZip? ===================================================== A. WinZip is not a PKWARE product. PKWARE makes its own stand alone program called PKZIP 2.60 for Windows. It does not require an external copy of PKZIP for DOS to invoke any command as WinZip does. PKZIP for Windows offers better compression and speed, as well as numerous other beneficial features. For information on PKZIP for Windows, please visit our WWW Page at: http://www.pkware.com. General Q. I forgot my password. What do I do? ======================================== 1. Try to remember the password. 2. Try passwords that are "close" to what you think it was. 3. Try mixed upper and lower case versions of your password. There really is nothing that can be done if you lose or forget your password. Don't forget or lose your passwords as PKWARE has no special means for "getting around" the encryption and may not be able to assist in the recovery of an encrypted file. YOU SHOULD KEEP A WRITTEN COPY OF YOUR PASSWORD(S) IN A SECURE PLACE. DO NOT TRUST YOUR MEMORY ALONE. Q. What does "Don't Know How to Handle" mean? =============================================== A. There are many different methods of compression. In the history of PKZIP alone there have been seven different methods to date. The .ZIP file format was designed so that additional methods of compression can be added as they are developed. In this way, the .ZIP file format will never need to be abandoned. If you attempt to extract a .ZIP file that was created with version 2.0 or higher with a lower version of PKUNZIP you will receive the message "Don't Know How to Handle" for every file compressed with a more advanced algorithm. If you attempt to extract a .ZIP file created with a version of PKZIP that includes a method PKZIP 2.0 does not use, you will receive a warning that will tell you what version of PKUNZIP you need. Q. PKZIPFIX. What is this program and how do I use it? ======================================================== A. PKZIPFIX is a recovery utility that is included with your copy of PKZIP for DOS and incorporated into PKZIP for Windows. It will attempt to repair a damaged .ZIP file and create a file called PKFIXED.ZIP. You can then attempt to extract from the PKFIXED.ZIP file. To run the DOS version of PKZIPFIX, enter the directory where the damaged .ZIP file is located and type: pkzipfix filename.zip You can then attempt to extract from the PKFIXED.ZIP file that PKZIPFIX will create. When PKZIP for Windows encounters a damaged .ZIP file, it will automatically detect the damage and will query whether PKZIPFIX is to be run. The resulting file will be called PKFIXED.ZIP. You can then attempt to extract from the PKFIXED.ZIP file. Q. What is PKZ300 and are you aware of this fake version? =========================================================== A. It has come to the attention of PKWARE that a fake version of PKZIP is being distributed as PKZ300B.ZIP or PKZ300.ZIP. It is not an official version from PKWARE and it will attempt to erase your hard drive if run. It is not a virus, but a trojan horse. It attempts to perform a deletion of all the directories of your current drive. If you have any information as to the creators of this trojan horse, PKWARE would be extremely interested to hear from you. If you have any other questions about this fake version, please email support@pkware.com Q. Do you offer a command line version that supports long file names? ====================================================================== A. Yes, PKZIP Command Line for Windows 95/NT is now available. This product will support long file names under WIN NT and WIN 95. Please see our WWW page for further information. Q. Do you offer a Macintosh version of PKZIP/PKUNZIP? ======================================================= A. Currently PKWARE does not offer PKZIP/PKUNZIP for the Macintosh environment, but we are considering developing such products in the future. Q. Is their a UNIX version of PKZIP/PKUNZIP? ============================================== A. PKZIP 2.50 for UNIX is now available. PKZIP 2.50 for UNIX initially will work on SPARC based platforms running Solaris 2.x operating systems. Other UNIX-based platforms and operating systems will be supported and available soon. Q. For which platforms is PKZIP currently available? ===================================================== A. PKWARE currently supports PKZIP on MS-DOS, OS/2, Windows 3.1x, Windows 95, Windows NT 3.51+, UNIX, and OpenVMS VAX and Alpha environments. PKWARE intends to support additional platforms and will announce these as they become available. Because PKWARE has dedicated the .ZIP file format to the public domain, it is possible for other people to write programs which can read .ZIP files. NOTE THAT THE PKZIP, PKUNZIP, PKSFX PROGRAMS AND THEIR ASSOCIATED SOURCE CODE AND SUPPORT PROGRAMS ARE THE EXCLUSIVE PROPERTY OF PKWARE INC. AND ARE NOT PUBLIC DOMAIN SOFTWARE PROGRAMS. We are currently aware of PKUNZIP compatible programs for a number of different platforms. A .ZIP file can be transferred to any platform for which you can find a compatible extraction program. Extraction and Compression programs not developed by PKWARE may not be completely compatible with the .ZIP file standard. Contact PKWARE for a list of platforms for which PKZIP and PKZIP compatible software is available. PKZIP for OpenVMS Q: I've used PKZIP for OpenVMS to compress some text files. When I transferred this .ZIP file to my PC and unzipped them, there were no carriage returns, but there strange binary characters after every line. Why is this? ======================================================================== A: There are many different formats for "text files" under OpenVMS. If you want to view or edit these files on a PC, they must be converted to "stream" record format, using the OpenVMS "CONVERT" command. To use this command, first create a file called STREAM.FDL, containing the following three lines: RECORD CARRIAGE_CONTROL carriage_return FORMAT stream After creating this file, type the following command, substituting the name of the file you wish to convert for "inputfile": $ CONVERT/FDL=STREAM.FDL inputfile *.* This will create a new version of the file, having the same text contents as the original file, but in the "stream" record format. This converted file, when extracted by PKZIP for DOS or Windows, will be a standard ASCII text file with CR-LF characters at the end of each line. Q: I compressed a text file with PKZIP for DOS (or Windows), but when I try to edit the extracted file under OpenVMS, there are "^M" characters at the end of each line. Why? ===================================================================== A: Since there are many possible text file formats under OpenVMS, you need to tell OpenVMS which kind of text file you have. After extracting the files with PKZIP for OpenVMS, type the following command for each file: $ EXCHANGE/NETWORK/FDL=STREAM.FDL inputfile *.* where 'STREAM.FDL' is the same 3-line file created above. This will create a new version of the file which no longer displays the extraneous "^M" characters when being edited. The "CONVERT" and "EXCHANGE" commands are standard OpenVMS utilities, and are covered in more detail by the appropriate manuals and help system. PKWARE Data Compression Libraries Q. Can the Data Compression Library create ZIP compatible files? ================================================================== A. The compression algorithm included in our Data Compression Library is incompatible with the inflate/deflate algorithms in PKZIP. For this reason, PKZIP for DOS and OpenVMS will not be able to decompress the file even in .ZIP format. PKZIP 2.50 for Windows, OS/2 and UNIX have an added feature that will allow reading of such a file created by our Data Compression Library. You may design your program to create files that meet the file layout specified in our Applications Note file (APPNOTE.TXT) included on the release disk and available on our WWW site, BBS, and forum on CompuServe. Q. I am using Visual C++ 4.0 (or above) and the static version of the data compression library. The following linker error occurs after compiling a multi-threaded program: "Default library "LIBCxx" conflicts with use of other libraries". What should I do? ================================================================== A. In the Visual C++ project settings, choose the Link tab. In the Input category, in the Ignore Libraries field, enter: LIBC.LIB Q. What settings is the PKWARE Data Compression Library for Mac OS compiled with? ==================================================================== A. The 68000 .LIB file distributed with version 1.1 of the PKWARE Data Compression Library for Mac OS is by default compiled with the following settings: Code Model = SMALL Struct Align = 68K 2 byte ints 4 byte doubles This library does not support far data and is called implode68K.lib. Q. Will the PKWARE Data Compression Library work with my compiler? Which version do I need? ================================================================== A. Here is a list of compilers, and the library environments in which they are compatible: Supported Compilers ------------------- Microsoft Visual C++ 32-bit (2.x-5.0) - Win 32-bit Microsoft Visual C++ 16-bit (1.x) - Win 16-bit Microsoft Visual C++ 5.0 for Windows CE - Win CE - currently in beta testing for SH3 and MIPS processors. Microsoft Visual Basic (3.0, 4.0) - Win 32-bit - VB does not support call back functions - our library will only do single file compression. Watcom C++/Symantec C++/Borland C++ - DOS 32-bit Quick Basic/Professional Basic 7.0 - DOS 16-bit Borland Delphi 16-bit (1.0) - Win 16-bit Borland Delphi 32-bit (2.0) - Win 32-bit Turbo PASCAL (6.0+)/Borland PASCAL - DOS 16-bit FoxPro for DOS - DOS 16-bit v1.10 FoxPro for Windows (2.5 & 2.6) - Win 16-bit - The current version of FoxPro for Windows requires a specially designed DLL known as an FLL. User would have to create own FLL using our static library. Visual FoxPro - Win 32-bit - does not support call back functions - our library will only do single file compression. Clipper - DOS 16-bit. Will work in protected mode using Blinker or ExoSpace. Pharlap286 - DOS 16-bit v1.10 32-bit DOS Extenders - DOS 32-bit - Examples include: PharLap 386, ERGO, DOS4GW, Borland Power Pack, DOSX, and CodeBuilder. IBM Cset/2 - OS/2 DCL Borland C++ for OS/2 - OS/2 DCL UNIX - UNIX DCL - available for SCO, SUN, LINUX, AIX, and UNIXWARE platforms. Metrowerks' CodeWarrior C/C++ - Mac OS Not Supported but Reported to Work ---------------------------------- Microsoft Visual Basic (5.0) - Win 32-bit - Possibly supports call back functions. Visual Objects - Win 16-bit FREE BSD - UNIX DCL - LINUX version AT&T UNIX - V R3.2 based version that runs COFF format binaries - UNIX DCL - SCO version. AT&T UNIX - B R4 based version that runs ELF format binaries - UNIX DCL - UNIXWARE version. Not Compatible -------------- PowerBuilder (all versions)