Cable and DSL modems occasionally need to be reinitialized..The modem may be causing your issue. The next time the problem happens, turn off the modem and the computer...Wait a couple of minutes, then restart the modem, let is reinitialize for a couple of minutes, then restart the computer.
Another thought, assuming you're using an ethernet card with the cable connection...try reinstalling your ethernet card driver OR check your ethernet card provider's website and download and install and updated version.
Hope this helps.
Here's my problem:
I have a 4-year old computer with Windows ME and a cable Internet connection. Sometimes I'll go to access the Internet and nothing works: browsers, chat programs, online games, anything. An hour later, things are working fine and I've forgotten about it. Sometimes the length varies: several hours, a full day. I can sometimes fix it by restarting my computer, other times I simply have to wait it out.
I've called my cable company about this, and they insist it's a problem internal to my computer. Whenever I call a computer center to look into this, they claim they'll have to do some diagnostic test that may or may not identify (not fix) the problem (but for which I'll be charged anyway). Naturally, I'm not too thrilled about this option, but I'm afraid this will get worse over time. Any suggestions?