Hello,
when I use Dopus to create a password secured zip file, the receiver can´t extrac it. He gets always an error message.
When I use Winrar in the same way, there is no problem.
What could it be? I use the attached configoration. May somebody can confirm this behavior?
Thanks for any hint.
gieri
test.zip (166 Bytes)
Which program(s) has the recipient tried to use for extraction?
Can the zip Opus makes be extracted with WinRAR on your machine? (It seems to work here, which implies the problem is with the zip tools or something modifying the zip in transit or on the recipient's machine.)
What's the error message?
Are the options in the screenshot tge exact ones you used? Some zip options will cause problems with tools that don't understand newer versions of the zip format, but the options in the screenshot look OK.
When creating the test zip in WinRAR, was the same password and data used? (Maybe the other end has issues with $ in passwords, for example.)
It may also be worth getting them to email back the zip file in case it is being modified in transit (e.g. by antivirus tools).
Hello Leo,
I connected remote to the recipient of my zip file and made some tests.
When I extract the password secured zipfile with the Windows internal extractor, I get the attached error. Windows doesn´t ask for a password.
When I extract the same file with 7zip, I get a popup where I can enter the password and the extraction goes well.
So it seems that the windows internal zip extraction can´t handle password secured zip file in the rigth way.
The error code 0x80004005 indicates a problem with the zip standard. It seems that a wrong crypto or compression was used for the file. Microsoft seems not be very variable with such parameter. May I have to use ZipCrypto and PPMd compression?
regards.
gieri
The "Standard" option is ZipCrypto.
PPMd isn't used by standard zip files (zipx files can use PPMd, but that would make things less compatible).
Creating a zip using the same options in your screenshot, then extracting it using Windows Explorer's "Extract..." option on Windows 7 works fine.
I also tried with your test.zip from earlier in the thread, and Explorer on Windows 7 extracts that fine as well.
So whatever is wrong seems to be a problem with the recipient's PC. I can't tell which version of Windows that is in the screenshot, so if they are running Windows Vista that might explain things. Otherwise, something weird is going on with their PC, and maybe antivirus or something is getting in the way, or some system components need repairing / re-registering.
Explorer prompts for the password like this:
Hello leo,
the recipient machine is a windows 7 pro.
So in fact that 7zip can extract it properly, it seems to be a corrupted system component 
Thanks for your help, I have to search in another direction again.
Best regards
gieri
I ran into a similar problem today. Client reports that he cannot unpack an AES 256 encrypted zip I created with DOpus 11.15.
I tried unpacking the file with Winrar 5.21, Total Commander, Win 8.1 Explorer in VM, all fail. AES 128 failed too.
Using Winzip 19.5 or DOpus for unpacking, no problems.
I then used Winrar to pack the files as zip with password, all programs: DOpus, TC, Winzip, and Winrar can handle this zip.
Packing in DOpus without password seems to cause no problems.
It seems that I should not use DOpus for any pw protected zip files because I cannot rely on someone else having Winzip (or DOpus) installed.
Am I overlooking something?
A lot of zip tools still do not support AES encryption in zip archives, even though it has been part of the standard for many years now. You should use "Standard" (weak) encryption if you need to maximise compatibility.
7-Zip is a free tool that can unpack AES encrypted zip files made with Opus, if you need one to recommend to people. (You can also use Opus to make a self-extracting archive, if you want strong encryption and find that is easier.)
Thanks!
I think I got confused because Winrar claims in the documentation
Not that I know what they are talking about but I recognized AES-256 and thought...
WinRAR supports AES in RAR archives. It may not understand it in Zip archives.