After having the above problem I was advised to use the following commands at the DOS prompt:
1. ipconfig /flushdns

2. netsh winsock reset

then unplug modem for 30 seconds to reset it and restart the computer. This remedies the problem but it then re occurs within hours and several times in the one day in a long day.
Contact your ISP...
They can do a line test to see if the issue is on their end.Thanks patio. ISP already told me the problem is my end. I run XP by the way. I spend a lot of time BROWSING share prices and STOCK market forums so I wonder if the constant refreshing of screens has any bearing?I've had to have my Motorola cable modem replaced...... TWICE.
Both times my ISP assured me that there was NO problem with the modem.....but both times, replacing the modem solved a problem. The last modem that was replaced, would take up to 20 minutes to reset, instead of the normal, 20 to 30 seconds.

I've also had two Intellinet routers, that would just stop talking to the modem. Both went back for RMA.
I may NEVER have an Intellinet router again. I've got several Linksys routers and one Belkin N router that just work Great.

So if you think you're having a modem problem, insist that it be replaced. It should be worth it to your ISP to keep you as a happy customer. Eh?



PS:
Bobconus, I use XP too, and I am on the internet, JUMPING from forum to forum for hours at a time. Just using your computer should NOT cause the problems you mention, unless, something is getting hot. Open your computer and make sure all your cooling fans are running and that nothing is getting overly hot.

Afterthought: Firefox is CONSTANTLY working to make their browser more compatible and efficient. Make sure you stay up to date with the Firefox updates. I'm currently running FF 8.0.1
Two add-ons that you should also keep up with is Shockwave and Flash for Firefox.
It also doesn't hurt to keep Java up to date too.Quote from: bobconus on November 18, 2011, 05:08:37 AM

After having the above problem I was advised to use the following commands at the DOS prompt:
1. ipconfig /flushdns

2. netsh winsock reset

then unplug modem for 30 seconds to reset it and restart the computer. This remedies the problem but it then re occurs within hours and several times in the one day in a long day.