Illustrator CS5.1 crashes when changing fonts

Question

Hoping someone can please help!! Every time I try to change fonts in Illustrator CS5.1, without fail it crashes. I'm on a macbook pro with retina display, OSX 10.9.4 and I have tried uninstalling then reinstalling the program and downloading the Adobe patches but my computer won't accept them. I've tried deleting the Illustrator preferences as well but nothing seems to work. PLEASE HELP?!!

Answer 1

dezine,
In serious cases requiring reinstallation, you should also use the Cleaner Tool, see 6) below.
But it may be something with fonts/font caches, see  Items 1) and 11) in the link in 5) below; these may be the most probable causes.
The following is a general list of things you may try when the issue is not in a specific file (you may have tried/done some of them already); 1) and 2) are the easy ones for temporary strangenesses, and 3) and 4) are specifically aimed at possibly corrupt preferences); 5) is a list in itself, and 6) is the last resort.
1) Close down Illy and open again;
2) Restart the computer (you may do that up to 3 times);
3) Close down Illy and press Ctrl+Alt+Shift/Cmd+Option+Shift during startup (easy but irreversible);
4) Move the folder (follow the link with that name) with Illy closed (more tedious but also more thorough and reversible);
5) Look through and try out the relevant among the Other options (follow the link with that name, Item 7) is a list of usual suspects among other applications that may disturb and confuse Illy, Item 15) applies to CC, CS6, and maybe CS5);
Even more seriously, you may:
6) Uninstall, run the Cleaner Tool (if you have CS3/CS4/CS5/CS6/CC), and reinstall.
http://www.adobe.com/support/contact/cscleanertool.html