Thanks for the quick response. Sorry for being so vague, I will now go through every thing I have done: On installing railmaster the first thing was that I had no chance of the trial, the software told me to activate right away. This I did and it activated OK. I selected yes to overide the windows security. I then followed the instructions with the software and had the error that the software could not connect to the elink. Checking the railmaster help file , I then checked the com port which was set ot 3 and then checked it was correct in railmaster and changed the speed to 115200. I tried at least 3 different USB cables and all the 4 USB sockets. One thing that has been the same all the time is that in the device manager 'other devices' shows 'unknown device'. This has not changed. The Ports USB serial port(com3) shows it is working correctly. I always run railmaster using the 'run as administrator' On checking some of the posts on the forum I tried some of your suggestions: In the railmaster .ini file. 1. check the 'restart elink on start =0' 2. Move 'Alternative comms' and 'Check controller' to the last lines of the file and set to '1'. I tried to upgrade the firmwire but again the error showed that it could not connect to the elink. I hope this is enough info, I have added 5 images, the best way that I could. If you require anything else please let me know. Peter /media/tinymce_upload/ae237b63fde28ca0e0c5524b0473d9dc.png/media/tinymce_upload/313494e831a8fca0f6d33860f6ae016b.png/media/tinymce_upload/4d8a71f0f0e56326908501a5a9532110.png/media/tinymce_upload/dd012ca846aee8affc9d7508e4cabde2.png/media/tinymce_upload/227eccb31d32143afabd05c533974bfd.jpg