Solving the mysterious MobileMe sync problem
Recently, I solved a weird problem I was having trying to use Apple’s MobileMe syncing — the problem being that refused to sync with an unspecified error. It turns out that my router has some sort of “black list” defence mechanism that is above and beyond the normal firewall. And for some reason it was blocking traffic to the MobileMe sync server and iDisk (idisk.mac.com). I have a Belkin ADSL modem/router and I was able to track down the command necessary to disable this “feature”.
You have to telnet into the router’s command-line interface using Terminal:
telnet 192.168.2.1
Login as admin using your admin password (it may be default if you never set it). Then type:
firewall set IDS blacklist disable
Case is important. If you ever reset the router, you’ll need to type this in again. I have a feeling this blacklist feature is responsible for a number of apps failing, including iChat’s video chat and some weirdness with Facebook chat as well. Routers are really the weak link in the Internet chain.