When you uninstalled the previous AV programs you installed did you use the removal tools from their website, if available. Uninstalling from the control panel sometimes leaves residual entries that would prevent Windows Defender from turning on.
Loopy, I've been able to keep my Avast by just running the cleaning tool CCleaner. You should really go that route!
Under the Applications tab, CCleaner defaults to assign checks in the checkboxes for "Utilities" for Avast! antivirus 6, Avast! antivirus 8 (you can see how many times I upgrade that prog, lol) , CDBurnerXP, IZarc, Windows Defender. These are just the utilities that CCleaner found on my computer. They will be slightly different on yours. There must be "Temp" files associated with these utilities that CCleaner purges from your system. Once purged TDBank is accessible.
Oh and I highly advise that when using Avast select Settings (top right corner) and the "Troubleshooting" link on the left. then check "Load Avast! services only after loading other system services. Your boot up time will be cut in half.
OH, and thank you for confirming to the 878,000 other users of the TDBank website that the problem is definitely with dealing with anti-virus programs!!! There is no where else on the web where this is stated!
