I am new to this forum but have been using AHP for a while on two different computers (not at the same time). Many of the problems reported here have also happened to me. Sometimes I have been able to solve the problem by erasing the interface module (sometimes even by unplugging it and removing the batteries for a few days). By far the best solutions have been to discover rules for writing macros, such as (1) don't start a macro with a delay block, and (2) don't start two macros with the same trigger. Other rules I have forgotten but they come back to me when something bad happens. I have had a lot of problems with conditional macros that have been solved by writting different sequences. I also have observed some random cycling. At Christmas I traced a rash of it to a neighbor with a new RC toy. Whenever he drove it past my house lights started going off and on. Changing the code for these lights from "E" to "I" seems to have solved that problem. (Maybe the toy broke?) Some of the random things may be due to noise in the USB (the computer and interface module are about 10 inches apart and the shielded USB cable is in a heap between them - all of this in a basement below ground level), or noise on the AC line (many filters have been installed on TVs, appliances, etc, but I may have missed some), or noise coming in the AC line from outside (the active 220 repeater is in the metal breaker box in the garage), or more RF sources in the neighborhood. So far the random nature of the noise problems is infrequent enough to be interesting but not annoying (except for the Christmas thing). I have never thought of erasing the register entries although early on I did reinstall AHP once or twice and erased all related file entries. The problems were much worse on the first computer using 98SE. The present computer uses XP Pro and AHP has only crashed it once or twice. Hope some of this is useful to someone. Your entries are interesting to me and I wanted to return the favor.