Remote Differential Compression IS enabled on the DPs so it isn't that. There is also no quota set on the server. I have discovered what the issue probably is in that the server has run out of space (Again!!) and that SCCM basically just eats up disc space for no apparent reason, we started on 250GB at Easter and now we are at 500GB and all we have are a few images and some programs. I did notice though in the ContentLib folder that there are lots of folders
that seem to contain more folders with the names of everything on our servers and within these are .dlls. Is this replication the reaso