Thanks to Jake, Richard and Ronald for their response to my query. The operating system and other software was "clean" installed a month or so ago and the wake up problem was there before. I have the latest software for all the peripherals, Epson scanner, Brothers all in one printer and Kensington track ball. I have removed all the USB peripherals except for the mouse and keyboard. The scanner and printer were connected thru a powered hub. I put the computer to sleep last night manually and it awoke this morning as it should, so the problem must be in the peripherals. Will reconnect the peripherals one at a time and see if I can isolate the culprit. This will take some time but I am sure the problem can be found. Harold