I have a single Win2008R2 database server failing to zip/unzip files properly. At our site there are two (going on three) Win2008R2 servers that use a WinRAR job to automatically compresses the nightly backup files, they all use the same scripts, EMC SAN's and have the same policies and securities set on them. Only one of these servers is failing. There are also 3 Win2003 servers that use the same scripts to do the same tasks and they never fail.
The files getting zipped start about 12GB and compress to less than 1.8 GB.
The server that is failing to work properly was commissioned in July of 2013 and started having these issues three weeks later. It is now failing 3 to 5 days a week and works perfectly the other days.