Check to see if you can flip the ends of the rails. If they are Dell branded rails then they should work with square or round holes. Check out the link here [URL]
Good Afternoon, We have a 4 post threaded circular hole rack as our primary rack. recently we received a donation of 2 Dell Poweredge 2950 gen iii. We came to find that the rails we had purchased for the server only support a squared holed rack. I have been surfing around for hours trying to find an adapter that would rectify this problem but i am coming up blank.  Does anyone here know if Dell or anyone else makes an adapter that would resolve this issue?  Cheers,  Dudebot12
Issues mounting my Dell Poweredge 2950 Gen iii