This particular issue came about due to a family member that was unable to check their HTTP E-Mail accounts after a new installation of SBC DSL either by accessing it via a browser or Outlook Express. After over two hours of banging my head against the monitor, I figured out the solution:
The "normal" way many DSL providers offer their service is using what is called "PPPoE" or Point to Point Protocol over Ethernet. Under normal circumstances, this is fine. However, it can cause issues such as this one. The fix? Download and run DRTCP available from DSLReports.com: https://www.dslreports.com/drtcp
The only setting you need to change is the "MTU" or Maximum Transmission Unit. This value needs to be changed to 1492. The default value for most Windows OS configurations with a LAN connection to the internet via a router or DSL modem is 1500. After applying this change and rebooting the computer, all should be well again with HTTP E-Mail.