problem w/ linked table permissions

This question involves SQL server as well as Access, so I hope that someone can follow.
I'm trying to give someone read and write access to a table in SQL server through a linked table scenario in Access.
I set up a new user account with datareader and datawriter permissions and made sure it went into the particular table as well. I also re-created the DSN on the user's local machine using this new login information. However, each time you open up the table after logging in using this info and try to edit a field, it gives a "Write Conflict" error and gives three choices: Save Changes, Copy to Clipboard, Drop Changes and of course, Save Changes is disabled.
We also tried logging in using the db admin account and it won't work.
Anyone have similar experiences with this? If so, is there a work-around so that you can edit data through Access?

Thanks in advance,
Colin

I just went over to her desk and she said "Oh, I can edit now" very casually. She made no changes, nor did I.
I hate Access.