Solved - I should read more!
@Walterf25,
thanks for your help. there were two problems stopping the app.
1. I had do not overwrite manifest clicked (due to flight mode) and then added a service, can't work!
2. The service reads the times from a file into a map. Forgot to open the file, hence your error.
The main problem was that I had no error, nothing, the service just didn't start. After correcting problem 1, I got your error and was able to solve it.
I am not finished but its getting there.
Thanks again for your help
ps. The variable "TimeSet" is actually only used to populate the label. The time is calculated in the sub ParseDates and is correct.
TimeSet = td.Hour * DateTime.TicksPerHour + td.Minute * DateTime.TicksPerMinute
Best regards
Mark