i work in a huge office with people using maya all day and these basic problems never happen for us. I've never once had to delete preferences and don't know anyone who has. When i see people on here complaining about the software, i can't help but think its some how user error.
I have problems with Maya, I can assure you it's not user error 
I have one machine that was custom built just for Maya, I never have any problems with it. I think most peoples problems stem from the fact that Maya works well on a pretty narrow sub set of hardware.
Install Maya on an machine with a AMD Radeon HD 6700 series gfx card and with the latest driver (well been several months since i did this) You can't select polygons in the viewport. User error no. Driver / Hardware incompatibility yes.
I believe Maya 2012 already has 4 hot fixes and 2 service packs to fix errors in the software that had nothing to do with user error.
On a home PC with mismatched and often cheaper hardware Maya can bit a pain in the ass to get running without errors. Bit unfair to say it works on hardware specifically built by a studio for Maya so all the other probs must me user error.
Might as well say if you have not spent at least $4000 bux on your machine don't complain. would be nice but it's a bit unrealistic for the average student. I could just reply to pretty much any Maya problem thread go buy yourself an NVIDIA Quadro 5000 and an INTEL Core i7-3960X Maya will run just fine, I've used it on this hardware never had a problem.
Maya does not run well on hardware it does not like, and there is a bucket load of hardware it don't like so these threads are going to keep pooping up.
Dave
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