couldn't find installable ISAM

Hi I am trying to cut and paste a table from one access db into another access db and I get the message :

couldn't find installable ISAM

what does this mean and how do I get round it , I have tried importing this table as well and I get the same message. What is causing this ? I have done this type of operation a few times before and it has always worked upto now.

Thanx Locutus

I had this error message once when i was trying to use a lotus spreadsheet as a database, I think it has something to do with file versions, or it may be a bug of some kind.