openclipboard failed (help please)

hi, I hoping someone will be able to help... in photopaint when useing any of the mask tool's, like the wand tool, or the freehand tool.....when I try to cut or copy then paste it....it will come up with this message "openclipboard failed" it works fine on the 1st time then i might need to cut something else out.....it will give me this message again...sometime I might enlarge the picture, then it will work ok again...but not the next time it won't....most of the time I close & when I open again the clipboard will work but again only once or twice...it will give me the same message...dose anyone know what it could be or what I could do plessssse! help!