Searchfunction logged off NAV

with searching do you mean Filter (F7) or the Search like Ctrl+F.
Crashed the window during the typing or if you press the "OK" or "Find First" Button :?:

Note:
if you have enabled the option "Find as you type", you should deactivate this under File -> Database -> Alter.
The reason: every keystroke will be send to the server and he runs a query like:
1. Entering the E
select * from XYZ where Field like %E%

2. Entering the s after the E
select * from XYZ where Field like %Es%

3. Entering the i after the s
select * from XYZ where Field like %Esi%

and so on. so, for this example: 3 queries .....