If you are using content classification - go to the classification menu and edit your classification criteria that is currently being used in your web post protection rule. Add a file condition for 'File extension' and add the .tmp extension. This excludes .tmp files from analysis.
If you want to be more granular with the exclusion go to the Windows client configuration policy - Content tracking > create an exclusion for your browser accessing/creating files in the .tmp directory.
Brilliant! Thank you for the assistance. I had checked all through the documentation that I could find, and I knew where I could do it in 9.x. Our ruleset is quite basic so i havent delved into it too deeply.