data report fail to open

Can somebody give me a reason to why when I open an old VB project that hasn't been touched for ages to do some mods. The project is failing to open up 1 of the data reports with the error log stating : -

Line 2: Class {C0E45035-5775-11D0-B388-00A0C9055D8E} of control de1 was not a loaded control class.
Line 0: The file C:\SOURCE~1\OPSNEW\vb\de1.Dsr could not be loaded.

I initaily thought it was down to a missing component or reference but have tried all relevant ones and still get this. Any help would be apritiated.