I'm REALLY not sure what is going on in your case but let's clean the whole thing out and start fresh.
Make a copy of your license folder onto a floppy (TCP5_USER->Licenses)
Throw away everything in Program Files->Jriver
In the registry, remove the J.River folders under HKLM->Software and HKCU->Software (resetting the permissions as described in
http://yabb.jriver.com/ice/index.php?board=2;action=display;threadid=210 if necessary)
Reinstall the PRO Server portion. (you might want to get the current version, it's a little newer than your version). Don't run licenseadmin or do a user install.
Copy the license folder back from floppy to TCP5_USER
Make sure TCP5_USER is shared full control for everyone if you are going to do network installs.
Run TCP5_USER->Setup.exe to reinstall the user portion on that machine. It will automatically find the licenses when you get to configwizard. Don't forget to put in a user name AND comment. If you can't get a license from configwizard, check licenseadmin in Start->All Programs->ICE.TCP admin to see if you have any users left.
You should be back up and running now...