[rosemaryknits]

I am having the same 535 authentication credentials problem. I have checked everything - logged in to my gmx account, making sure that the imap/pop box was properly clicked and that my password was functioning, it all is fine. I double checked the settings in Calibre (although I have changed nothing...) and it all checks out as fine. I even double checked to see that my gmx email is still on the preferred list in amazon. However, I suddenly can't send books.

Anyone have any suggestions as to what else to check? Thanks in advance.

Nevermind, I just fixed it. DUR. Sorry!!!

Here's how - I have no idea why this worked but - I clicked "preferences" then "sharing books by email" then "use gmx" (on the right) and then filled in all of the boxes. Then, under "mail Server" I made sure that the full email address was in the slot, instead of just "@gmx" Tested and voila, all fixed.

I still don't know why this information needed to be redone, I have made no adjustments to Calibre.

Anyway, I'm back to sending stuff to my paperwhite, yay!