Polar ZIP Component :: FAQ

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Tehnical Q&A

What are the limitations of the trial version?
The trial version of Polar ZIP Component is completely functional and expires after 30 days. This means that you get to experience all the functions present in our release version for 30 days. After trial period expires, component will throw an exception when you attempt to call it.

Is Polar ZIP compatible with ZIP standard?
Polar ZIP is 100% compatible with PKZIP 2.04g file format. ZIP files created by Polar ZIP can be used by PKZIP 2.04g and vice-versa.

What compression ratios does Polar Zip offer? Is there a set ratio or is it adjustable?
There is no fixed compression ratio in PolarZIP - the actual ratio depends on the type of the data being compressed. Due to the algorithms used, files with a repetitive data structure (i.e. images with large black areas) result in smaller archive files than those of a more random nature. If you want to adjust the intensity of compression, Polar Zip allows you to choose from ten different compression level - from simply storing files to using complex methods resulting in the highest compression ratios.

Why are some anti-spyware programs detecting Polar ZIP as spyware?
Our product is free from spyware and viruses. We believe the problem is in anti-spyware software so you should contact the manufacturer of your anti-spyware program in order to resolve this issue.

What do you get within the Polar ZIP?
Polar ZIP Components:

• Polar.Zip.dll – Polar ZIP dynamic-link library (Installed in WIN/SYS directory)
• PolarZip.ocx – Polar ZIP ActiveX control
• Polar.zip.dll - Polar ZIP class library for .NET
• Polar ZIP Documentation:
• PolarZip.chm – Help file (MSDN-like look & feel)
• License.txt
• ReadMe.txt – Information about installation, registration, etc. Polar ZIP
• Sample Files:
• Source codes for the samples written in:
• Visual Basic 6.0 (using ActiveX)
• Visual Basic 6.0 (using DLL)
• Visual C++ 6.0 (using ActiveX)
• Visual C++ 6.0 (using DLL)
• Borland C++ Builder 4.0 (using ActiveX)
• Borland Delphi 4.0 (using DLL)
• Borland Delphi (using ActiveX)
• MS Access (using ActiveX)
• MS FoxPro (using ActiveX)
• Source codes for the ASP samples
• Demo Browser (for easier browsing of the samples)

What additional files do I need in order to use Polar ZIP ActiveX control?
In order for the Polar ZIP ActiveX control to work properly on the customer's machine, he must have the following files installed:

• polarzip.ocx
• MFC42.DLL – Standard Windows system DLL for Windows 98
• MSVCRT.DLL – Standard Windows system DLL

The .OCX file must be registered on each user's machine. To register an OCX on the user machine, use the regsvr32.exe utility available from Microsoft and distributed with every Windows operating system. To run it, type the following at the command prompt on each user's machine:
regsvr32 polarzip.ocx
Our ActiveX controls require OLE2 support to be installed on a machine. In order to run an application containing one of our controls you must ensure that OLE2 has been installed on the user's machine. If your client's machine has older versions of these files, you will need to update them.

I am getting an error when trying to install the final distributed product. At the very beginning of the setup process, I get an error message saying that a PolarZip file is missing or not registered properly.
You should try to register the component manually with regsvr32.exe utility to see whether this is a dependency problem, or the installation script fails to correctly register the OCX.

The development environment I use is ASP and I would like to add the data encryption feature to the application I am developing. How I can incorporate Polar Zip in my ASP source code, as to support data encryption?
There are two ways you can achieve this using Polar ZIP.
You can use standard zip encryption by setting password parameters:

PolarZIP1.UsePassword = True
PolarZIP1.Password = "PolarZIP"

or by creating Self-Extracting archive.
The difference between these two methods is that in the case of Self-Extracting archive, the encryption method used will be AES. AES is a far better option, as encryption defined by the zip standard can be deciphered within a few days.

How to create multi-part zip files directly to a hard drive?
Here is the example for creating multi archive zip files:

// multi archive on hard disk
// each file is maximum 100 kb
// e.g. if archive.zip is 340 kb then it will be split in
4 files (100 ,100,100 ,40 kb )
// with names arhive001.zip,archive002.zip,
archive003.zip, archive004.zip
ZipArchive pZipArchive = new ZipArchive(@"c:\archive.zip");
pZipArchive.AddFiles(@"c:\temp", new ZipFileFilter(""), 100 1024);

For unzipping multi archive files you need to combine it first.
Here is the example:

ZipArchive pZipArchive = new ZipArchive(@"c:\combined_archive.zip");
pZipArchive.CombineSpannedArchive(@"c:\archive001.zip");

(note: for spanned archive string, argument for CombineSpannedArchive
method you could put any spanned archive file e.g. "c:\archive020.zip")

Does Polar ZIP support the Advanced Encryption Standard (AES) when creating self-extracting files?
Yes, it does. Polar ZIP is the first compression tool in history to introduce the most secure encryption for your data, using the full strength (up to 256-bit key) of the Rijndael algorithm.

Is there a way to use the AES encryption within PolarZip without creating a 'SFX' file? What I want to do is to compress and use AES encryption on a file that I can later uncompress to a memory buffer.
This only can be done with a combination of Polar Crypto on Polar Zip.

I am using Polar Crypto 2.5 and Polar ZIP 5.0. I want to combine both these applications: I have made a VB application which prompts users to select multiple files; then it encrypts them all, makes a ZIP file with Polar ZIP and then creates a self extracting EXE. The EXE file is sent to a user who does not have Polar ZIP or Crypto, so I want the user to be able to unzip and decrypt the files.
Polar ZIP uses AES encryption only when creating a self extracting file. To use the encryption simply enable it and set the password. Now after you create the self extracting archive it will be encrypted. Another option is to use Polar Crypto's ability to create self-decrypting files. The results are the same as with Polar ZIP, only the file won't be compressed.

Does the Polar ZIP library support disk spanning?
Yes it does. Polar ZIP can create multidisk archives and/or even a multifile archive on one, non-removable disk. Files from a multifile archive on a non-removable disk must be merged into one, single zip file before extracting.

Can I extract the SFX binary ZIP file and place it in another directory besides the current one?
You can choose a directory to unzip SFX archive to by setting the Polar ZIP property SfxDefaultUnzipToFolder.

Is there any way to turn off the messages while extracting SFX files?
Yes, just set the SfxShowDialogs property to False. By doing this, you will ensure that the extraction will be done “in silence” i.e. without displaying the Self-Extracting dialog.

Is it possible to use a custom icon for the exe file created from the zip file?
The default icon that is displayed when the self-extracting file is created in the self-extracting binary file (UnzipSfx.bin). You cannot change the default icon that is assigned to self-extracting files but this feature will probably be supported in future versions of the Polar ZIP product.

I wrote my program in VB 6.0 using only the DLL calls. When I distribute my program is it enough to give out PolarZip.dll or I must distribute the .OCX file as well?
If you used only dll calls you only need to redistribute PolarZip.dll.

How could I use your control to unzip a specific file, place it in a new directory, and then name it differently?
Using events like FileStartedCompressing and FileStartedDecompressing you can control file names and paths that go in or out of the archive.

Is it possible to get PolarZip to extract files to the paths stored when StorePaths = True? I particularly want this when the original folder structure does not exist on the target computer.
Polar Zip will create folder structure contained in an archive. Also it will create destination folder, if it does not exist.

I would like the self extracting file to create the default extraction folder if it does not exist. This would eliminate users having to manually create the folder, before clicking on the self extract file.
You can choose directory to unzip to by setting the Polar ZIP property SfxDefaultUnzipToFolder.

Is it possible to install the polarzip dll in a directory other than system32?
PolarZIP.ocx, PolarZIP.dll are the Polar ZIP Component's re-distributable files. These files may be in the Windows system directory, in the computer's path or for WinNT and Win95, in the directory specified by your application's Per Application Path key in the Registry Database. So put PolarZIP.dll wherever you want but be sure that you have registered it (with regsvr32.exe utility) later.

Your site mentions that Polar ZIP uses advanced encryption methods. However these encryption methods are not supported by other zip programs. Can I create a zip file using Polar Zip that uses the OLDER zip encryption method consistent with PKZip 2.04 standards? I'd like to encrypt my files, but do not care to make self-extracting exes or use an alternate encryption method.
128-bit AES advanced encryption is applied only with the self-extracting .exe archives. When you use ordinary .zip archives standard PKZip 2.04 encryption is used.

Can we use Polar ZIP to do more than one concurrent ZIP operations?
Yes, you have to give each ZIP operation different temporary path, for example, when beginning new zip operation create folder of random characters and set it as temporary path and after operation is completed you can delete created folder.

I purchased Polar Zip 3.0 component few years ago and I need to use it for some code maintenance on an old program, but I can not find the license key to reinstall it. Can I use only .dll file?
That version of Polar Zip is no longer available in the download section. You just need to register the .dll file with RegSvr32 and it should be working.

When one of the files contained in the archive has a “[“ character in filename Extract method returned error 233 'no matching files found' even though List method correctly identifies it. What is the problem?
Brackets [] have a special meaning in filtering files. With them you can include a whole range of names instead of typing every single name. For example ‘file1[a-c].doc’ means ‘file1a.doc’,’file1b.doc’ and ‘file1.c.doc’. To solve it simply write ‘Zip1.UseSpecialWildCards=True’ and ‘[‘ and ‘]’ do not have a special meaning at all. Thus file1[a].doc really means file1[a].doc. By default UseSpecialWildCards is False.

What is maximum single file size that can be included in a zip file?
Maximum single file size that can be included in a zip file is limited to 2GB.

Can Polar Zip for .NET extract or list archives with the following file extensions . and .arc?
Polar Zip for .NET deals only with zip archives that are compatible with the PKZIP format.

Is there a way to create a folder in a zip light file? I would like to zip files NOT with the original folder, but would like to create one and add files to the zip folder.
It is not possible to create a folder in ZIP file conventionally on your disk. However, you can catch FileStartedCompressing Event and change every file name that represents font ?(there is a function to detect this ) and simply append the folder name in front of it. So the FileName will be "arial.ttf" when event handling starts and then you change it to "fonts\arial.ttf