Recently an increasing number of users registered complaints with the helpdesk about MS-Office documents opening very slowly. - This was the case for both Office XP and Office 2007 users.
First I thought that that was yet another case of the well known behaviour that MS-Office shows when looking for a template. But both a network sniffer and filemon did not show that MS-Word was not looking for anything it couldn't find. Both CPU and I/O were very low, but Word (or Excel) hung. - Opening a file from a running office application worked ok.
Googling for the problem showed that the problem was pretty common and the suggested work-around was to disable DDE when opening a file.
Unchecking „use dde“ and modifying the application call by adding a „%1“ really did help.
But this had a minor side effect (every office document opens in a new window) and did not really make me happy. So I had to get to the bottom of the problem.
The long hang gave me enough time to see which hwndTo / hwndFrom call hung.
But that did not help to identify the culprit. X-Spy did the trick:
While the system hung, I refreshed the window- and process lists in x-spy and noted the windows handle from ddespy.
Searching for said windows handle in x-spy showed that dde communication had timed out and what the offending process was:
naviclient.exe
→ screenshot here
Killing naviclient and naviagent immediately cured the problem.
Our Help Desk people uninstalled the program on all PCs (via SMS) and stopped the service on the machines where it wouldn't uninstall.
Problem solved.