Cannot open saved zip files extracted from Outlook Mail

Hi Everyone,

I've created a small C# application which extracts attachments from outlook emails and saves them to a network location. I can open all of the saved files except for compressed files with "zip" extension.

Files with the "zip" extension can only be opened/extracted via Windows Explorer. If I try to use WinRAR, I get the following error: "The archive is either in unknown format or damaged". WinZip does not work either. If however, I open the email within outlook manually and copy the zip file to my PC, I am able to open the zipped file using WinRAR, WinZip as well as windows explorer.

Part of the code used to save the attachment is shown below.

        Microsoft.Office.Interop.Outlook.MailItem _mailItem;
        ...
        ...
        _AttachFileName = _mailItem.Attachments[j].FileName;
        _TempAttachmentFile = Path.Combine(_tempFolder.Path, _AttachFileName);

        _mailItem.Attachments[j].SaveAsFile(_TempAttachmentFile);
        ...
        ...

Has anyone faced a similar issue with compressed zip files? If so were you able to resolve the issue?

Any ideas or help on this will be appreciated.

Thanks
Navnit

Hi Everyone,

I managed to get to the bottom of the issue. The problem I was having wasn't caused by the code I posted earlier.

After posting my issue on the forum, I had a closer look at what I was doing within my code and found that at a later stage of my application code, I was converting the attachment into base64 string for some internal processing. This was eventually getting saved back as a file to the final destination folder. It was during this final saving process I accidently reduced the data by a byte.

Code causing the issue:

FileStream outFile;
..
outFile.Write(binaryData, 0, binaryData.Length-1);
..

Fixed code:

FileStream outFile;
..
outFile.Write(binaryData, 0, binaryData.Length);
..

Apologies for the confusion.

1 Reply

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navnit mudaliar15y ago
Hi Everyone,

I managed to get to the bottom of the issue. The problem I was having wasn't caused by the code I posted earlier.

After posting my issue on the forum, I had a closer look at what I was doing within my code and found that at a later stage of my application code, I was converting the attachment into base64 string for some internal processing. This was eventually getting saved back as a file to the final destination folder. It was during this final saving process I accidently reduced the data by a byte.

Code causing the issue:

FileStream outFile;
..
outFile.Write(binaryData, 0, binaryData.Length-1);
..

Fixed code:

FileStream outFile;
..
outFile.Write(binaryData, 0, binaryData.Length);
..

Apologies for the confusion.