It means undetermined error. In practice, since LSVDBS has been pretty stable and has no known bug, it means that someone linked R/W to the disk where the archives are stored, XEDITed a couple of them to add or remove some stuff, and didn't bother to tell LISTSERV to refresh its database index. For performance reasons, LISTSERV doesn't try to detect this kind of things which are, of course, not allowed. If you have archives which can be searched through the database functions, they must be modified using the GET and PUT functions, which refresh the index as necessary. Eric