starting to reveal my ignorance ! I don't really know how I have MCLR set this is an area I do not understand well. I already had trouble because I initially thought I was using MPASM when in fact i was using the melabs version and find it difficult to translate between the two ! I will have a look at the line you provided and try to work out what it should be on my system. As a point of intertest I have bought god knows how many books on PIC programming and have always felt that the config business is very poorly explained most of the stuff my aged brain has coped with but not that. I'll have another look at Melanies post on config and try to work it out together with exactly what MCLR does !