Request expired can happen if the time or time zone gets out of step between PC and devices. Double-check that.
If you are in UK or Europe, maybe summer time error somewhere?
Thanks for reply. No, no difference between clocks.
I am trying to use the aldiko 2.2.3 ereader app. It always says device isn't authorized. However after all my trouble last night the ADE program on my PC suddenly displayed my HTC as being authorized. Despite this, I could not get the book to open.