Hello Anatoly,
We are sorry to know that. We will check and help you to resolve it.
- Could you please confirm the version of AVG Tuneup?
- Have you tried to reinstall AVG Tuneup and check this status?
- Please try to remove AVG Tuneup from startup list in Task manager and check it.
- Share us the screenshot (https://support.avg.com/SupportArticleView?urlname=AVG-Create-screenshot) of the page which shows 100% disk usage.