Finally sorted out the problem.  In the master page I had the EnableViewState set to False, but in the acutal page I had this set to true, so I would have thought it would override the master page setting.  Well apparently it doesn't, once I set the viewstate to true in the master page it started working.

Could anyone tell me if this is right I thought you could override the master page setting.

Anyway thanks for those that tried to help much appreciated.