I have a strange issue at my workplace and it is driving people mad.

I recently installed a draytek 2820 to act as our main router for our BT business ADSL connection, replacing the bt business hub that was broken.

Everything is fine except we get random timeouts on https page authentication.

The place this shows the most is on accessing our remote exchange email on RPC over https - it just stops working intermittently.

If when this happens you try and access outlook web access over https the it constantly prompts you for authentication but http works fine. At the same time other https logins do not work and time out.

I have the https management option of the draytek turned off and have changed the assigned port away from 443 anyway.

it is driving me mad trying to track this down..

any help would be appreciated.

Have you got multiple WAN IPs set up on it? If you've used WAN IP Alias to do it, untick the Join NAT IP pool option, with that ticked it'll possibly be switching IP addresses while accessing sites which will mess up an HTTPS connection like you're seeing.

Or is this happening when connecting in to the router?