As a retired electronics technician who did most of his last work repairing 80286 and 80386 motherboards to the component level, I had seen an awful lot of freaky problems, but the one I ran into the other day takes the cake.
Last Friday, I was finding myself having trouble logging in at secure websites (HTTPS URL's). When I would enter my username and password either things would just hang up and time out or all I would get back would be an empty document (without the usual browser warning that it was empty). As time went on, the problem only got worse. It was not until Tuesday morning that I finally solved the problem, simply because the explanation was so off the wall as to be virtually unthinkable.
Having two identical computers (except that one runs on Mandrake 10.0 and the other on Mandriva 2006) turned out to be a blessing. The problem was happening with both of them, with or without the router. (It was also failing with Firefox, Epiphany, Konqueror and Seamonkey web browsers on both machines.) I was rather loathe to go between the two machines, simply because I do not have two monitors, mice and keyboards which makes going from one to the other a mess of dealing with massively tangled cables. By Tuesday morning, the problem was beginning to affect non-secure websites as well, where, though I was able to log in at a forum at here at LinuxQuestions, I was not able to post to it. It was after that when I had my "ah! ha!" moment. I called my ISP and demanded a replacement cable modem, since they upgraded me to a faster modem the very morning of the day my problem began. With a new modem being the only thing in common between the two systems, that had to be the problem. I faced considerable resistance from the ISP's technicians, but finally they gave me a new modem.
Much to their amazement (and still to my bewilderment
), that solved the problem. We are still scratching our heads over that one. How could a modem be so selective in what it screws up???
Moral of the story: Never rule out the oddball solution -- it just might be the one you need.
(in spirit, anyway)