I am new to raid and have just bought an external raid box (with 2 hard drives and very limited set-up instructions) which i have set up as raid 1. This is showing as just one drive in windows so how can i be sure that the information on this drive has been copied to the other drive in the box?
If you do not get an error from the RAID driver during boot, you can be certain it is on both drives.
Go into the RAID application (either during startup or later) and see which drives are assigned. It will let you know if there is an issue with one of them. (Mine will flash a critical error when one drive goes bad).