Consider the following scenario. You create the Multiple lines of text property for the columns that are in a Microsoft Windows SharePoint Services document library or picture library. Then, you type content that contains more than 255 characters in the Text field of a new document.
In this scenario, you receive the following error message if you type more than 255 characters in the Text field of a new document:
Field Name can have no more than 255 characters.
Note The placeholder Field Name is a placeholder for the name of the column in the list.
This issue occurs because of a design limitation in the following programs:
Windows SharePoint Services
Microsoft Office 2003 and earlier versions of Microsoft Office
The OLE property streams that are associated with Office do not support more than 255 characters. Additionally, if you change the character limit for the Text field to more than 255 characters, you cannot demote the OLE property in the Office document.