Assume that a custom list in a Microsoft SharePoint Foundation 2010 site or in a Microsoft SharePoint Server 2010 site contains a multiline text column. If the data size of the custom column is more than 100 kilobytes (KB), only the first 100 KB of the data is indexed when you perform a crawl on the SharePoint site. Additionally, you receive the following error message:
The filename or extension is too long.
To resolve this issue, apply the following hotfix packages:
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.