I too, among every one I know using AVG Free edition have been experiencing problems downloading the updates. I am a dial-up user and it constantly is telling me I need to open my browser manually and it is already open. In the last month I have been lucky to get the download on first try maybe 1 time. I am also having the same problems today March 31 mentioned above.
Someone sent me this information to try. They said they researched the problem and this was the solution. I did not try it until today, (and I still couldn't update.) so maybe todays problems are of a different nature.
They suggested to open the url.ini file found in the Grisoft folder, in note pad. Delete what is there and put
[SERVER_NAME]
1=free.grisoft.cz
2=ftp.grisoft.com
3=www.grisoft.com
[SERVER_URL]
1=http://free.grisoft.cz/softw/60/fe
2=ftp.grisoft.com/pub/softw/60/fe/
3=http://www.grisoft.com/softw/60/fe/
Actual URL=3
in its place and save it. I did this but everytime I try to access for an update it changes the number 3 back to a 1., Being you can not contact Grisoft unless you are using a pay version I guess they are wanting to make us all pay.
Will keep watching this site to see if anyone finds out the solution to this problem.