We have been having the same problem for over a year on the Canada01 Listserv. Eric suggested that the cause of the"insufficient storage" error was due to memory fragmentation and could be cured by more frequent IPLs. Initially we set up a daily STOP REIPL in the wakeparm file but have since increased it to four times daily. The fragmentation appears to be caused by a few high activity lists with large files and I usually put those lists on hold if I am not going to be in a position to check on listserv (like over a weekend when I am out of town). Occassionally, listserv will bomb on that error only a few hours after a REIPL so I am not sure if fragmentation is the only problem. However, the REIPL process keeps it up and running for much longer periods than we ever achieved without it. Good Luck, Les