On May 20, 2014, at 10:58 AM, Cory Smelosky <b4 at gewt.net> wrote: On Tue, 20 May 2014, Cory Smelosky wrote: After a reboot: Pack cluster size is not 1, 2, 4, 8, 16, 32 or 64. PC=120324 PS=030344 OV=000006 M5=004000 M6=004200 SP=041236 R0=000026 R1=143161 R2=143161 R3=000000 R4=000002 R5=041350 The disk is 1048778 blocks. I created a 512M image and copied it bit-for-bit to the disk. I think i'll just go SYSGEN 4.8 and wait for my cleaning tapes to get RSTS/E working. How about copying the image back off, to see if the disk controller mangled it? The message you quoted says that the content of block 1 is invalid (the pack label). Judging by the code, what it found is 0143161 rather than a valid PCS. I wonder if your partitioning disk controller is misbehaving. BTW, sufficiently recent versions of RSTS (including the one you have, given that message) should handle a 2 GB disk directly (at DCS=64). That way you don t need to mess with partitions. paul