I have never actually made an incremental back-up. Just the whole OS partition every now and then. My reason is that the only changes I would have made are possibly adding a new program that in most likelihood, I don't need. But I alwsy have three images (the most current and the previous two) so can always check which program to add should I need it.

Spoke with the broadband provider yesterday, mentioned the issue. he said that if one computer (wireless) and the phones can access the site, then the issue is not with the ISP hardware / software. There is another possibility. I run an old / free version of ZoneAlarm and that has recently been popping up an 'important upgrade' message. Since the upgrade is not free, I just cancel the message. I had a look at ZoneAlarm and cannot see how to bulk delete some of the 4000+ entries. It could be that one of those is causing the issue.