How do I get rid of about:blank?
It sounds like you have a homepage hijacker, at least I’m assuming it now has “about blank” as your homepage. Ilknur K gave you some excellent free programs to try. You can also reset your homepage Tools/Internet Options/ & then Home Page, of course that will only be temp probably until you get rid of the problem by running all those great programs. Just make sure you update each of them before you run scans on your computer. AVG is really good but superantispyware & malwarebytes will find things your antivirus won’t. Good luck!