I completely uninstalled all NI Software and then reinstalled NIDAQmx 9.2.3.
Now MAX sees my DAQ card, but the Test Panel doesn't work.
I had to rename c:\WINNT\system32\nidmfpan.exe.manifest to nidmfpan.exe.manifest.bak to get around that problem.
I thought I post this here in case someone else runs inthe same problem.
Ralf