When system was upgraded to OS/390V2R10 (from V2R7) some programs began abending with U4038 on report files. If programs are recompiled with NOADV option the error goes away, or if a BLKSIZE=134 is added to the JCL for the report files the error goes away. Recompiling several hundred programs is not a happy thought, but adding the BLKSIZE is wrong, these files are really 133 bytes long. Anyone shed any insight on this and any solution? Thanks...