The first problem I would suspect on a disk where list stuff is being logged in the one known under the poetic name of "DISK m(cuu) IS FULL". Given a return code 113 from EXECIO, you can issue a HELP EXECIO command and discover that 113 = 100 + nn, where 'nn' = 13 is the return code from the disk I/O operation. If you have a look at the CMS paper doc (which are rather unwieldy, so let's say you have a look at DMSBWR ASSEMBLE instead), you will find out that rc=13 means DISK FULL. It is an old IBM standard return code by the way. I am not surprised that moving the disk to another volume does not solve the problem. Some huge mail is being received that fills up the log disk, that's all. And in that instance 1.5l would have transferred the mailfile to the postmaster and held the list with notification being sent out. Eric