Can anyone tell me what the error message "Access Violation Exception at 0x0076414C" means?

WD6 had started throwing up this message after I drew a rectangle on a page of a site I'd been working on for a few weeks. Now it throws up the message whenever I try doing anything (drawing a shape, clicking for the text tool, deleting a layer) on either the file I was working on or a new blank file. WD6 loads and will also load that particular file or open a new document - which can be viewed and clicked on, but when a tool is selected and the page clicked or when a layer is selected the error message shows, an error report is sent and WD6 closes.

The problem has been passed to Xara & now Magix nearly a week ago, but does anyone have suggestions on what this could be related to?

Magix gave me a system check to run, but the results didnt seem to show anything that would be responsible. Then suggested I install the latest update & patch, but when trying this I receive a message telling me that I already have the latest version & there's no further updates. I've insterted the WD6 CD and clicked repair, but that didn't make a difference. So I've also uninstalled and reinstalled the programme, but that hasn't made a difference either. Lastly I've changed the location of the backups folder - but that's not made a difference either, though it needed doing anyway to direct to the partition with more space on. I received back a fixed file from Magix and from what I gather, the error can no longer be reproduced at their end - so it looks like it's something on my system, but Im out of ideas on what else to try.

Im falling behind now on getting the project finished, so Im happy to try out any further suggestions people may have. Thanks in advance!