URC6430, URC6440: Using SimpleSet.com, can I reset my Simple remote back to the factory settings?

Yes you can.
Using www.simpleset.com press the Restore Remote button, and select the remote you have.You will then be asked to download a new settings.bin file and copy and replace it on your remote.
Then, the Simple 3will be restored to the state you bought it in.
Please note: before you programme the remote you first have to setup the region again.