Trainz

I am trying to apply the 43434 to 44088 patch and keep getting this error:
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Ready to install from local patch file.
Current version: 43434.

Checking for available disk space for patching.
Unpacking patch file...
Patching from 43434 to 44088...

Failed patch command: "C:\Program Files (x86)\Auran\TS2010\bin\jpatchl-w32.exe" "C:\Program Files (x86)\Auran\TS2010\bin\plugins\TNISpeedTree.dll.pbk" "C:\Users\JOHNFA~1\AppData\Local\Temp\file1796101\data\bin\plugins\TNISpeedTree.dll.diff" "C:\Program Files (x86)\Auran\TS2010\bin\plugins\TNISpeedTree.dll"
An unknown error (4792486) occurred while patching file bin\plugins\TNISpeedTree.dll

Failed to apply the patch: 43434_to_44088
Patching aborted.
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Patching has always gone just fine before.

I downloaded the patch again to make sure it was not corrupted but same problem.

Windows 7 Pro 64 bit. 1 TB hard disk (lots of room left on the drive). 6gb RAM, I7 920