1. When I try to re-open the file, I get the notice that someone else has the file open - even after shut down and I'm pretty sure no one else has the file open.

OR

2. It opens the file but after a few minutes, it returns the same "Cannot read memory error..."

Your situation can be caused by quite a few things. I would recommend hanging out at support.microsoft.com and running a search for your error message as you see it on your screen. You will see there are quite a few items that can cause this message.

I would suspect a corrupt file, a poorly written macro or VBA, or possibily a bad picture or table in the file. Can you save to a TXT or RTF file? I would try something like that. You will loose some formatting but this might get rid of what is causing the memory error. You can rebuild sections of your document after you open your RTF or TXT file and re-save as a doc file with your formating.

Microsoft also mentions that this message can occur when one of the following files becomes corrupt:

Mso9intl.dll

Msohelp.exe

Msoffice.exe (this may or may not be installed on your computer)

I would try running a search on these files, renaming them, then putting your Office install disk back in your computer and running a 'repair'. Do not reinstall, just repair missing or damaged files. A reinstall my just 'see' that the file exists and not repair it.

Hope this helps.