Just to clarify, these are the steps I used unsuccessfully to "Extend/Renew" the Avast Free software, which is now announcing expiration in 4 days:
1. Press the "Extend" button in the 4 day expiration warning banner. This brings up a page with no SELECT button for the Avast Free Antivirus.
2. Press "Activate" button in the lower left of the Avast menu screen. Press the SELECT button for the Avast Free Antivirus. Hit the X in the upper right for the next two screens (note that there aren't any "No Thank You" buttons present on those two screens). The main menu screen pops back up with the expiration banner and 4 day countdown still present.
3. Use the Windows 7 Programs and Features area and select "Uninstall". This brings up an Avast menu screen that says my license is about expire, but no worries, just press the Activate button and the license will be renewed. Press the button, the menu screen stays there for about 3 seconds then closes. Nothing else happens. Bring up the Avast menu again, the expiration banner is still present.
4. Use the Windows 7 Programs and Features area and select "Uninstall". From the Avast menu screen that pops up select "Repair" This downloads and unpacks fresh files and installs them and prompts for a Restart. Restart the computer, bring up the Avast menu, expiration banner is still present. Try steps 1 and 2 above again, no success.
5. Use the Windows 7 Programs and Features area and select "Uninstall" and remove Avast. Restart the computer, then use the Web installer to install Avast again. When the menu is brought up, the expiration banner is still present with the 4-day warning. Try steps 1 and 2 above again, no success.
At this time, it would appear that (at least for me) Avast Free is currently broken. I'm game to wait and see for the next 4 days to see what happens...