Web Filter Lite not allowing any HTTP traffic

I have the same issue as the poster of this thread (http://forums.untangle.com/web-filte...p-traffic.html). We have an Untangle server that has been working fine for years. Suddenly Web Filter Lite will not allow any HTTP traffic for computers that are not in the IP bypass list. IP bypass list computers are not affected. It doesn't matter if the website is on the pass list or block list or neither, the behavior is the same. The browser acts like there is no website at the address, it doesn't give the Untangle block page. Firefox says "The connection was reset". Of course if I disable Web Filter Lite, all browsing works normally.

We were running 9.3 and I updated it to 9.4, no change in behavior. Has anyone else seen and resolved this issue without replacing the Untangle server itself?

Thanks,
Michael