Can you furnish us with some extra details bd like
What operating system?
Have you installed anything new lately?
Do you have any antivirus installed?
Does the problem occur at any particular time?
If you don't have any AV try going to
trend micro and run the free online AV check.
If you have installed something then try uninstalling it.
I am sure you will be bombarded with suggestions if you provide some extra info.
FSD