Is norton.com Safe?

After expiry date,virtually impossible to remove. Several programs disappeared from my computer, without a trace; many others suffered missing or corrupted files,etc and had to be completely reinstalled. Received email offering to scan my computer in return for my completing their Customer Survey. They claimed my coimputer was unprotected, performance was poor, and 28 threats had been found. They offered to block and remove threats and rev up my computer, for £60.subscription. Unprotected? Obviously they failed to detect Microsoft Security Essentials and MyWOT, both services provided for FREE.