Interesting problem. I haven't worked with World of Warcraft much. However, if all else is inobvious, it can help with an intermittent failure problem, to do a general scan for adware / spyware / malware / viruses. I can recommend these utilities, all free of charges, with no costs, and without drawbacks:
1. Go to www.spybot.com
, download Spybot Search & Destroy 1.6, install it, update it fully, run a complete scan, and tell it to Fix whatever it finds wrong.
2. Go tohttp://us.trendmicro.com/us/products/personal/CWShredder/
and download by clicking the icon to ""Remove CoolWebSearch" (saving it to e.g. the Desktop, where it will be easy to find). Run CWShredder by double-clicking on its paper-shredder icon, agree to the license, click Scan Only, watch as the results scroll up... if all entries say "Not present", then nothing of the sort is present... but if one IS found, choose Fix on this scan or the next scan (if the next scan, start the scan with the Fix button instead of the Scan Only button.)
3. Go tohttp://vil.nai.com/vil/stinger/
and download Stinger at the link next to the number 1. , below the question "How do I use Stinger?" Save to a location where it will be easy to find its orange and yellow square icon:
and double-click on it to start it. Configure it in its Properties to scan boot sectors (as well as all the other things), select scan area (probably just C:\ would do), and start scan. It may find nothing, but if it finds anything, that's cause for concern.
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