Hi @Dom ,
What's the type of your account(POP, IMAP, Exchange)?
Could you find the draft in the Web Mail?
I looked at the email today and see it is completely blank.
As I know, there's no option in Outlook that could make the draft message disappeared and just turn to blank. In order to further analyze if your original draft is disappeared, please first search for it in your Web Mail.
If the original draft couldn't be searched out, in the point of Outlook client, archive policy may cause the message move to other location as Manu mentioned, which may cause you couldn't search out it. It's suggested to check the setting of auto archive in your Outlook (File>Options>Advanced>Auto-archive setting).
Also, accidentally deleting it permanently also may cause the message couldn't be searched out. If you are using exchange account, the option of "Recover deleted items from server" could recover the items that be deleted recently(choose the “Deleted Items” folder> click Recover Deleted Items from Server). Otherwise, I'm afraid the item couldn't be recovered.
Besides, if the original draft could be found in your Web Mail and the issue only happen to the Outlook client, it may be related to the synchronization error between client and server, it's suggested to create a new profile and re-add your account to check(Control Panel>Mail>Show Profiles>Add>type a profile name>re-add your account).
Hope this could be helpful to you.
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