Several people have reported that AVG Free v8 has recently begun triggering a TeaTimer warning about an unlisted Registry change. The change is not in the current official TeaTimer Whitelist and so requires the user to agree the alteration. The TeaTimer popup lists the change as "avgrsstarter" with no details of the old or new values - so it is difficult to see what it is attempting to modify and why it is required.

I just got the same warning myself - and decided to track it down.
The "avgrsstarter" registry change relates to the following registry setting:

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\Notify\avgrsstarter]
"DLLName"="avgrsstx.dll"
"Startup"="AvgStartup"

Avgstarter doesn't exist as a file - it appears to be an internal reference inside the avgrsstx.dll file. The avgrsstx.dll file resides in the System32 folder and is named as the "AVG Resident Shield Starter".

The TeaTimer popup happens when the AVG automatic update system wants to force a restart of Windows after a major program update. If the change is allowed it is followed by a popup message from AVG that a restart is needed to complete the update - with a countdown that has only one button - OK to proceed. AVG Free is currently updating from 8.0.176 to 8.0.233 which is a major program version update that requires a restart. You do not get the "avgrsstarter" registry update message from TeaTimer if you do a manual install of the new version - you just get a request by AVG to restart Windows to complete the update.

If you see this TeaTimer popup you need to allow this Registry change or this update will not activate until your next reboot - and file version conflicts may occur if you attempt to run a scan before the reboot. AVG appears to have altered the way a forced restart is requested - as I have never had this problem before. For now you need to choose ALLOW and you can also tick the Remember this change box.

I suggest that this item should be added to the official TeaTimer Whitelist to avoid future problems.