Haven't played CFS3 in long time.  Tried to run tonight but game fails with Callsign DB failed to initialize then another error saying mission failed to load.  This is right after the opening screen when I get the menu or option display.  DOn't know what this means or how to fix.
Help appreciated!

Thanks for replying.  The message was Callsign DB not initialized.  I couldn't even find Callsign anywhere.  I will delete uisel.xml.  When I tried Quick Combat the P-51D was selected.  WHen I click Airplanes the next menu shows a a long list of numbers (123456789) instead of what I assume should have been other airplanes to select from.  I had DL'd and installed various game enhancements and other AC.  I haven't used the game for about 2 years and can't remember what I did. 
WOuld I be better off uninstalling and starting over?
I tried uninstalling but can't find the uninstal.exe.  Tried ADd/Remove and get a message saying the game had been previuosly uninstalled, yet it is still there!.  At this point I don'tknow how to uninstall it!

By cfs3path\info do you mean cfs3path is the foder where CFS3 is installed and info is a sub folder? 
I think I found some folders in the Aircraft folder that don't belong there.  If I remove them is there another file I need to delete so it will get rebuilt when I start CFS3?
I looked in Program FIles\Microsoft Games\COmbat Flight SImulator 3\info and it did not contain callsign.dat.  It only had chatbase.htm, filter1.dat, filter2.dat,fltuser.xml,and opareas.dat.
Appreciate your help.

I found an aircraft subfolder "3mp_f8f2 was empty with only its sub folder "Sound".  The empty folder should have had an aircraft.cfg plus other stuff.  I also noticed some aircraft subfolders do not have all four subfolders Model, Pylons, Sound, Texture.  Is that ok?
I also found the subfolder "Shared" in the Aircraft folder.  This subfolder was part of the CFS3_GunWeaponsPak download.  I must have copied there unknowingly.  I deleted both of these from Aircraft, and wiill go back and repair them later if I can get things running.
I also found no copies of country.xml, cutscenes.xml, or pilotconstants.xml in the main CFS3 folder!  I must have screwed up on of the installs of the 17 Nationality paks, so I re-installed all of the nationality paks again.  I'm getting ready to restart CFS3 and see what happens.