I reported the same sort of problem (though it's not intermittant for me) http://community.axosoft.com/forums/thread/13458.aspx
If you have firefox and IE7 try pasting the links into them - I found it works for firefox but not for ie7. It seems OnTime sets up a "webserver" on that port and under 127.0.0.1 which is usually the local machine - though it seems that under some of MS server configurations it doesn't work. for example if you are using MS ISA server with a proxy. Also 127.0.0.1:80 is often the the domain website under MS small business server.
I did find one workaround if you have the same situation and cause as me.
I think Axosoft have decided this is not their problem - tell them if you disagree.