ERROR #124 (0x8510007c) Memory Invalid Block

Hello Epics,

There are some steps that you can do fix this. First update all chipset, video and sound drivers.
You can follow these steps for help updating your chipetset drivers. http://www.playtool.com/pages/chipsetdrivers/chipset.html

After you update the drivers do a scan disk and defrag of your computers hard dirive.

If this problem persist do a memory diagnostic of your RAM and check for bad RAM.
http://www.memtest86.com/

Detailed instructions on how to do all these steps can be found at:
http://us.blizzard.com/support/article.xml?articleId=21025