my computer is infected... - Windows

1)i cant apply "system restore application"

2)whenever i typing chinese, my system will be broken

3)anti-virus says my computer is fine

4)i am not authorized to restore my computer(1)

5)i am the only user of this computer

6)i cant use "safety mode"(not authorized)

7)my rundll32.exe does not work

PS.i was forced to install a application yesterday when surfing on net...

please help me...

tell me what to do

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