[solved] Error after uninstalling Navision 3.6 client

We had a strange experience last week after uninstalling Navison 3.6 client:
Some application didn't work anymore and there was always an internet explorer script error. Also problems when printing from Outlook and when using mmc.
Quite similar to
http://www.mibuso.com/forum/viewtopic.php?t=21371

By the way, reinstalling the client worked.

My questions to this:

1) Is this a 3.6 problem only? There is a KB article on this.
http://support.microsoft.com/kb/816598/en-us

2) What's your experience with this? Must be quite a usual problem, not because of uninstalling Navision for good but while performing a (technical) upgrade.

Your input on this will be very appreciated.

Thomas