Since you are obviously using either V05.06 or V05.07 Yup. 5.07. It has Mentec branding! (only the last two versions of RT-11 have the RT11ZM Monitor), you can use the VRUN command to support giving LINK all 64 KB of memory. Naturally, you will probably need at least 256 KB of total physical memory on even a PDP-11/23 (to run RT11XM as well as to provide the needed extended memory to provide LINK with the full 64 KB to run in) although 128 KB might do in a pinch depending on which device you use for the system device. Thanks. I'll look in to VRUN. Any good results (or bad) to report? How much physical memory do you have? Jerome Fine