When attempting to check for incoming email with Earthlink TotalAccess 2005 I get a message that the instruction at 0x77f8910e referenced at 0x016b08f4 and memory could not be read. This was apparently triggered by mailclient.exe. Does anyone know of a fix for this?

Problems like this are notoriously difficult to resolve. What it generally means is that it couldn't read some unspecified information from an unspecified place in your system memory (RAM) or on your hard disk. This could be caused by defective RAM or a defective hard disk but, more often, there's something wrong with the software installation.

The easiest way to resolve this that is most likely to work is to remove the Earthlink software, reboot, delete all of your temporary files*, empty your Recycle Bin*, run Scandisk*, run Disk Defragmenter and then re-install the Earthlink software again.

* Optional but it is recommended for the most thorough process.