In the userprofile dir %localappdata%\assembly\temp subfolders are created using local storage space from workstations.
This is a common feature from .net and is called "Shadow Copy".
"Shadow Copy" can be deactivated.
Edit the File "adxloader.dll.manifest" in the Outlook Addin install folder
Set the property of "shadowCopyEnable" to "false".
Upon saving the file, "Shadow Copy" will not be performed anymore.
The "Shadow Copy" feature is used to refresh applications even when the application is not active.
This is useful on terminal servers.