Hi DannyV1 and welcome to the forum.
First I need to know the following:
1. What is your OS, 32 or 64-bit?
2. What version of Avast did you install? 5.0.677?
3. What product of Avast did you install? Free, Pro, AIS?
4. What other security software do you
currently have or did you have
in the past on this machine including antivirus (AV), firewall (FW), and other security programs? If they were in the past, how did you remove them (the vendor's uninstaller's tool or another way)?
5. Have you made any changes to your machine lately? If so, what did you do?
Thank you.