Avast filling up drive in temp folder

[REDACTED]

I'm having a serious issue with Avast over the last week. 

Something in Avast is creating a file in the Appdata\local\temp\_avast_\ that just grows and grows until it fills my entire drive (900GB).  I cannot delete the file until I hard stop the Microsoft Outlook process that is running.  Once I delete it, and start outlook again, it then starts filling a new file. 

I tried updating Avast to the new release for 2016, same thing happens.  I made sure my MS Office has the current patches, and Windows has current patches.  I ran a virus scan and MBAM scan, and nothing was found.

Help please?!

[DavidR]

The _avast_ is where avast unpacks/sends files to be scanned, on successful completion of the scan the contents are removed.

What other security based software do you have installed (antivirus/anti-spyware/firewall, etc.) ?
If you are using MBAM Premium I suggest you exclude that folder in MBAM settings.

Can you give some examples of these files file name including file type.
A small screenshot of the folder would do, so long as we can see some of the file names and file types.