Kevin, We (Tom and I) found the problem: the sourcing of the GEMPAK environment by the LDM user's profile-file caused the regutil(1) utility to use the ZLIB(3) library from the GEMPAK package -- with the consequent results. We modified the LDM user's profile-file to have an appropriate definition for LD_LIBRARY_PATH *before* the GEMPAK environment is sourced -- resulting in regutil(1) finding the right ZLIB dynamic library. I rebuilt and re-installed both your 6.12.4 and 6.13.6 distributions. You should be good to go. Regards, Steve Emmerson Ticket Details =================== Ticket ID: ITT-588398 Department: Support LDM Priority: Normal Status: Closed =================== NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.