Start/Programs/iSeries Access for Windows/iSeries Access for Windows Properties
On the General Tab, the version and service pack level is shown.
My laptop is at Version 5 Release 4 Mod level 0 Service pack SI29771
You can find the latest levels here:
http://www-03.ibm.com/systems/i/software/access/windows/casp.html(Looks like i will be updating my own!)
I always mention the service pack because IBM's support line will insist on it if you report a problem.
Service pack installation will often clear up unusual behaviour, especially if the user installed something that conflicts.
Under point 2, you said logged in as user/admin. Did you try using a different iSeries user profile with more authority?
Failing that, is there anything else unusual about this pc?
Barry