Can't connect to server error msg when trying to update

Just installed avast internet security 7 and it went well. The only thing I can’t do is update program or virus definitions. Every time I try I receive the following error msg - can’t connect to server. I have no issue with my internet or connecting to any site.
Any ideas why I can’t connect to update?

what AV did you use before avast?
have you removed it?
did you use the vendors removal tool to clear any leftover files that may conflict?