No email on client computers

[BeerBrewr]

Hi all. Stuckin a deep rut.
I have 4 computers hard wired w/ switch. Host computer is connected to the net. (USB Satellite) All Win XP Pro. Host computer functions normally. The others can share files and browse the Web. Problem is that they cannot access the email server or login to a secure site. eg. online banking.
I isolated 2 computers, formated and reinstalled the OS on both machines. to no avail.
The network was runnin smooth for about 3 yrs. I haven't made any changes other than upgrades to software. None resent.
Also disabled firewall, antivirus & spyware stuff.

 

[folken]

Are you using ICS (windows internet connection sharing) on the computer w/ the modem to share the internet to the other computers?

 

[riser]

Secure sites today require 128bit encryption, IE 6.0 at least.

That sounds like it may be your problem..

 

[BeerBrewr]

Yes. All can browse and share files. There no changes that I made. All software was up to date. The only thing that I think could had happen, my bro inserting his jump drive on Thanksgiving Day. It was shortly after that one of the clients lost secure sites. Kind of like the domino effect.
I use Nav, Spy sweeper & Zone Alarm. None gave no problems or indications of anything going on.
My resolution was to delete all partitions and reinstall everything.
All is restored and working.
Thanx Folken and Riser for the replies.
Sure wish there was an easier fix. I just finished yesterday. Lessons
learned. Again