Patterning

I have a louver forming tool that I insert it into mysheetmetal part, when I try to pattern it I get a rebuild error:(unable to create instances for the pattern. Try again bydecreasing the number of instances or the distance between theinstances.) My louver is .025 wide and my pattern is at adistance of .050 and 6 instances. I tried for the hell of it tomake the distance .040 and the instances 5 but the same error comesup. I just used this same louver on Monday and all was good. Anyideas?
Thanks,
RobSolidworksGeneral