I was trying to run the National Instruments example code to read a tdms file and I got an error saying something about an unrecognized compiler and to run mex -setup. So I typed "mex -setup" in the command line and it immediately closed matlab and it won't reopen even after a computer restart. Any help would be appreciated.
I found the problem, Kapersky Anti-Virus 6.0 quarantined Matlab.exe after running the mex -setup command. After restoring the quarantined file and disabling the proactive defense everything worked fine.
Perhaps the preferences are damaged. So try to move (not delete, keep the original as backup) the contents of the folder "C:\Users\YOURNAME\AppData\Roaming\MathWorks\MATLAB\R20XYa" (with the obvious changes) to another location. Then try to start again.