Zip Encryption Creates 32 Bytes ZIP Files

User Help, discussion of features, issues, and general topics about Uranium Backup.

Moderators: Davide Costantini, Romana Romandini, Andrea Ciotti, Administrator

Posts: 3
Joined: Sat Jul 09, 2016 12:24 am

Zip Encryption Creates 32 Bytes ZIP Files

Postby bellcomp » Sat Jul 09, 2016 12:47 am

I am attempting to set up an incremental file backup that is encrypted. I have successfully configured the backup without the encryption using ZIP compression (a daily to a NAS and a weekly to an external hard drive).

As soon as I enable the "Encrypt zip file in this destination" option in the backup configuration, the ZIP file that Uranium produces is not correct. The backup takes about the same length of time as without the encrpytion enabled, but the ZIP file says it is only 32 bytes (both in the Uranium log and on disk). If I try to restore from the ZIP file, the restore fails with an error that says "Restore completed with errors: Invalid archive file. -Native error: 00035".

What is more interesting is that this only seems to happen on the full backups (that I know of). Once a full backup has been completed (with a corrupted ZIP file), the incremental seems to run correctly (at least the ZIP file is much larger than 32 bytes).

As soon as I turn the encryption off, the full backup works again. I have filled in the encryption password in the General Options.

Is there something else I have to do to make encryption work properly or is this a bug?

Posts: 3
Joined: Sat Jul 09, 2016 12:24 am

Re: Zip Encryption Creates 32 Bytes ZIP Files

Postby bellcomp » Tue Jul 12, 2016 7:42 pm

I've done a little bit more testing on this issue.

If I exclude some files from the backup (putting the data set around 30GB), it will run successfully.

When running with a larger data set (40GB+ ), the backup will correctly create the ZIP file, but seems to stop as soon as encryption should begin. The log says the backup is successful, but it is not.

I have reproduced the issue on another computer, simply by using an incremental file backup with ZIP and encryption options and a data set of about 60GB. If I reduce the amount of data on this other computer, it seems to work fine as well.

I am using the latest version of Uranium 9.2.1 (Build 5900).

Posts: 3
Joined: Sat Jul 09, 2016 12:24 am

Re: Zip Encryption Creates 32 Bytes ZIP Files

Postby bellcomp » Tue Jul 12, 2016 8:35 pm

I have done some more testing on this.

If I reduce the data set (to around 30GB), the backup will run successfully. If I add more files (it tested it at about 50GB and 60GB), it will not work correctly.

The backup appears to be working correctly initially (with a larger data set) and creates the ZIP file. But as soon as the encryption should begin, the backup completes (saying it is successful) and leaves a 32 bytes ZIP file. This ZIP file cannot be restored from.

I have tested this on another computer and the symptoms appear to be the same. I don't know exactly at what size the backup starts to fail, but I think it's somewhere between 30GB and 50GB.

I am using the latest version of Uranium, 9.2.1 (Build 5900). Both computers are using the Gold edition. One is running Windows Server 2012 R2 and the other Windows 10 Pro (version 1151).

User avatar
Posts: 144
Joined: Wed May 04, 2016 9:30 am

Re: Zip Encryption Creates 32 Bytes ZIP Files

Postby cinzia.mancini » Thu Jul 14, 2016 2:59 pm

Good morning,
thank you for all your tests.
We know the problem.
It is in a fix in one of the next release: the combination zip and encrypt creates a good zip file, but the decryption gives error.

Have a nice day.
Cinzia Mancini
Nanosystems S.r.l.
Assistenza e Sviluppo software

Return to Technical Support ENG

Who is online

Users browsing this forum: No registered users and 1 guest