In my game Mechanics don't seem to be fixing or inspecting anything, they just say 'roving' all the time. I have fully trained them, increased their salary but nothing seems to work. Every time I have click on the ride and click the 'call mechanic' button for the ride to be fixed/inspected.
This is mostly annoying for animal enclosures.

I was hoping there would be someone who would be able to help me out.
If you have any ideas please post them below.

try setting a working area for them. it probably wont work but its worth a try

I have tried all the combinations I can think of.

I found that setting a patrolling area on a ride's queue path makes inspect and fix that ride automatically, which fixes my problem, but means I need 1 mechanic for every ride I have, which is expensive and time consuming.

fire them all and re-hire them, have you tried that?

yes I have tried that.

also I have tried opening & closing all of the rides. I have created about 6 new parks, tried it in the scenario editor.
nothing will work.

i think your game is buggered.....

The thing is that I got the game in June and it has been working fine ever since. I having changed anything files etc. or downloaded any coasters, scenary etc.

I would try using the RCT3 Cheats. Just a thought.