Boxster window
 

I have a 1999 Boxster 2.7. Two problems. When I travel over a bump the drivers window drops by 1/4" and the interior light comes on. Often is corrects within a second and returns to normal. The drivers door window only drops 1/4" when parked if I slightly operate the door pull in/out to lower the window and it will not remain down un less I hold it manually. To close the door I must then hold the pull slightly the slam the door then the window returns to top.
Is the fault of a faulty 'Door handle microswitch' 996 613 12600?

Yes; that is what the problem is. I just did this job, and it isn't bad. Need to remove the panel, and getting the door lock microswitch out is a bit fiddly, but overall, not a bad job. You may be able to repair the unit, altho I could not with mine. I bought a used one from another forum member, and it works just fine.
Here are some useful links:
Pelican Parts Technical BBS - Powered by vBulletin
Window comes down but goes back up again??? - 986 Series (Boxster, Boxster S) - RennTech.org Forums
Troubleshooting window sensor - 986 Series (Boxster, Boxster S) - RennTech.org Forums