When I span up an ubuntu client a couple of months ago I decided to use Firebird to access my Hotmail email account. Without really thinking about what I was doing I changed the default setting of the Account set up process to use POP as the email protocol.
I then happily used Thunderbird without issue. Sometime later I used the web interface of Hotmail and discovered that searching on specific terms gave back far less search results that I was expected. After a bit of investigation it turns out that Firebird has a default option of deleting email from the server 7 days after having been downloaded when using the POP protocol. This meant all the historic email I had in Hotmail now resided on my Unbuntu device and I could no longer access it from either the browser interface or other email clients.
I naively started to look at what programs existed out there to upload emails into Hotmail without success. Some time passed and I ran into an article comparing the POP and IMAP protocols. The former coincided with my understanding of the protocol, however, I realised that I had a gap in my knowledge of IMAP. It turns out that it’s a synchronisation protocol that ensures all devices have the same view of mail and folders rather than the classic client/server type of affair you get with POP. A far better overview is published here.
In Firebird I just saved the downloaded email into a separate folder from the inbox, and deleted my Hotmail account. I hen set the Account up again but made sure I didn’t alter the default of IMAP. Once synchronisation had completed I just drag and dropped the email messages in the saved folder back into the newly created inbox. Left it a couple of hours and hey presto – all my email is again available in Hotmail’s web interface (albeit as soon as I access a restored message it’s date/timestamp is updated to now meaning the message appears newer than it actually is).