rk,
Whenever posting questions on these forums, please give us as much information as possible about your computer. We need the operating system, processor speed, amount of RAM installed, brand name of the computer, (if there is one), and any EXACT error messages you are receiving. The more information you give us, the better informed our answer will be. Enough of that, back to your question.
It sounds like the other connection is trying to rewrite the dial-up on occasion. Not knowing your operating system makes this difficult, but have you tried removing/disabling the cable connection from the Control Panel/Network Connections icon. Likewise, remove the other account from your e-mail properties, so it doesn't try to connect to another server first.
Hope this helps and give us some more info please.
Grif
My internet connection setting keeps changing every time I start my computer. I used to have cable internet and everything worked great. I have moved and am stuck with dial-up. The settings when I click on the internet setting, under automatic configuration, keeps changing to putting a check mark in each box under proxy server. When these boxes are checked, I cannot connect to any web site. I can receive e-mail, but cannot view any images in HTML. Also, it changes my password. I have to keep changing them back to be able to use the internet. What makes my settings change? And how can I stop it!

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