[This note has been sent to the following InterNet address(es): [log in to unmask]] On 12/9/95 (Note: UK date format - dd/mm/yy) I posted the following to the new SIGSYSMAN list but it was suggested that I post it here also : I know of a site that tried to upgrade to MPE/iX 5.0 and after hitting some problems (which I won't go into here), attempted to reverse the upgrade and return to 4.0. The return should have been made easier by the bootup from the specially attached SCSI drive with the 4.0 operating system already installed which worked like a charm on a practice system. However, when the system came back up, it seemed to have still got some MPE/iX 5.0 commands available although error messages were generated when they were executed. It turns out that there was a problem with NETBASE which had allocated some programs and the reboot had NOT deallocated them. This raises a couple of points : 1. I had been led to believe that doing a RS would reset the SPU and flush all remnants of the previous system and an RS was done in this case. 2. It appears the command RE (which eventually solved the problem) actually resets everything (except critical values for control purposes), e.g. SPU,Power supply,control monitor , external buses ? The question is, when should you use RS and when RE ? Cheers, John Dunlop ([log in to unmask])