When attempting to open/close a Revit file and/or closing the software you get a message "Revit Encountered an improper argument".
To fix this issue:
- Run your windows updates. Look in the optional updates and make sure you do not have any windows 7 updates or c++ updates, if you do, make sure they are included in the updates getting installed.
- Clean out the temp folder located under your user folder C:\Users\Your user profile name\AppData\Local\Temp. Delete everything, if it won't let you delete an item then click the skip button.
- Reboot your machine.
- Uninstall the Revit software by making sure you clean out the registry and any folders associated with the software by following these steps; http://blogs.rand.com/support/2012/07/quick-guide-on-uninstalling-autodesk-software.html