Do you let the disk check complete? I'd be backing up now just in case.
Besides that no probs. I have Avira, MSE & Windows Defender no alerts from them. Also I have DiskCheckup, no warnings there. The drive is maybe 1 1/2 year old. Have XP home.
I know there is an issue with Avira and Windows 7 with a scan disk at every boot - might be worth removing that to check.
Hmmm ok, when I first installed Avira it didn't do it.