My PRS-300 is apparently not authorised to me!

[Fifer72]

After importing eBooks to my eReader successfully, I had to reinstall W7.  Now when I try to transfer eBooks from my laptop to my reader I get the following - Warning.  This eBook cannot be transferred because the Reader is authorised to another user.

As I am the only person who uses both the laptop and the eReader, how can I resolve this, without loosing anything from the eReader (21 books) or my Reader library (6 books)?

Any help most gratefully received!

[Fifer72 · Accepted solution]

I have managed to sort my problem!  I should in future, try a bit harder for a bit longer!  And I managed to save all my downloads too!