Can you post the full details of the avast alert (if posting a url change the http to hxxp to break the link) or attach a screenshot of the avast alert.

This usually means that you have an underlying infection, that is trying to connect to a malicious site to download more malware, etc. Avast is preventing that from happening, so you don’t want to stop it as such.

This probably needs further analysis by a malware removal specialist:
Go to this topic http://forum.avast.com/index.php?topic=53253.0 for information on Logs to assist in cleaning malware. Use the information about getting and using the tools and attach the logs here, not in the LOGS topic.

There may be some delay due to differing time zones (2:18am in the UK and 3:18am Europe) and availability of the volunteer malware removal specialists.