Cannot complete the request because the item was removed from the gallarey

hi

when i am trying to add the webpart to a page the message pops up Cannot complete the request because the item was removed from the gallarey

i successfully build the solution and then i deployed the package(wsp)to Sharepoint and populate the webpart in the Gallery but when i am trying to add this webpart to a page  i get  this message  Cannot complete the request because the item was removed from the gallarey

Thanks 

sal