I've recently begun migrating some documents that require a freeform "description" metadata field. I have this field defined as multi-line text with When I bring in a new document to my library and get SharePoint's dialog box to enter all the metadata fields, I get an error that the field has limit of 255 characters. Sure enough I have 318 characters in my description.
Same document in Datasheet view: I can copy/paste the exact same block of 318 characters for which I was getting an error into the appropriate row/column without any difficulty. When displaying the field, it's not truncated @ 255 characters, I can see all 318.
Is anyone aware of the reason the dialog box errors out but datasheet view allows the appropriate entry?