Endpoint Encryption

I'm getting a PGP Warning 'An error occurred: Unknown Harsh number' when I try to decrypt 24MB file sent to me by a user who is on PGP version 10 licensed copy. Another user who is using PGP version 8 licensed copy can decrypt the file with no problem.

If I encrypt the file myself I can decrypt fine. It's just this one file only.

see att.

I'm sure it will come to no surprise to you that 6.5.3 is very old, and that there have been many improvements to PGP since them.  This includes using improved, more secure hashes.  What you are most likely experiencing is that the person sending you the file is also signing it.  By default, more recent versions of PGP use newer, improved hashes in the signature that 6.5.3 cannot handle, and therefore cannot decrypt the file.  In addition to the possibility of your changing to a more recent PGP version, you can probably handle this problem by either having the sender of the file not sign it, or him or her changing their PGP settings to use only the older and weaker hashes of MD5 and SHA1.

Do you need further assistance with this?

FYI, if you simply need to decrypt this one file you could always install the Symantec Encryption Desktop trialware version (formerly PGP Desktop). It's good for 90 days for full functionality. Once the 90 days is up you will no longer be able to use any of the paid for features such as PGP Virtual Disk, Drive Encryption, or File Share Encryption, etc.

Here is the link to access the trialware:

https://www4.symantec.com/Vrt/offer?a_id=109690