We have a weird problem with a workstation that has had the Netware client

As long as the Netware server it used to log in to is running, all is well.
As soon as the Netware server is turned off, and you right click on any
file in Explorer, Explorer hangs for 3 - minutes. It appears to be
explorer hanging - similar issues if you right click on the file.

It appears to be something to do with the File Type or right click menu
context, but I haven't been able to track down a fix.

Can anyone tell me what the workstation is trying to access on the old
server, despite having the netware client uninstalled? I assume there is
something that needs to be cleared out of the registry, but I haven't found
it :-(

Any help or pointers would be much appreciated.