I am using many mods and After a certain amount of play time, Morrowind crashes and displays the error message:
"MapTextureManager : RepairMapRender : entry in tes grid does not have a cell."
I assume its an issue with a mod, but i am not sure what the message means or where to start looking for the problem.
Help?

Does no one have any idea from what that error message might derive from?
I don't expect specifics but id like a clue if you have one.

Wild stab:

I think there are 3 records associated with every coordinate on the map grid: CELL, LAND, and PGRD. Maybe you have a mod that defines a LAND or PGRD outside of the Morrowind map, but it does not define a CELL for that location, so Morrowind is complaining.

I would think you'd be able to find the mod quickly using the old http://www.mwmythicmods.com/argent/tech/bin_srch.html method. And then look inside it to see what it defines for those record types.

Post your Load Order,
and are you using the Code Patch?

Thank you, the error has been located.

It would be nice to know what you found, if others ever encounter it.