Acrobat Acrobat will not save to a network shared drive

I have users when they open up pdf documents from a network shared drive make edits and then save get an error.

The error that pops up is "The document could not be saved. Cannot save to this filename. Please save the document with a different name or in a different folder." The document than is renamed in the folder to something like aaa999 as a file and not with a pdf extension.

The user can save locally and drag the file to the network share but this increases their workload.

Network Share drive is on a Windows Server 2012.

User is on Windows 7 Pro.

Using Adobe Acrobat 8. (We have software that is business related that we can not upgrade to newer versions of Acrobat).

The option of Security (Enhanced) and protected view are not options under preferences.