Hi
If nothing is working with you- no antivirus, spy ware, ad ware etc. then you can format your PC, but be cautious to backup your data on an external medium like cd-dvd, otherwise you would be running about to get solutions to recover data from the formatted partitions.
Sometimes there are hidden virus or spy ware which are not traced by anti virus softwares, but they keep spoiling our PC. These come with free sites from where you download any software or music of kind.
I am suggetsing to format because nothing is working with you and i have faced this situation twice and the best solution which i could figure out was formatting (backing up data first).
Hope this proves helpful!!
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