I am using Windows Live Mail on Windows 10. Like others, I have found that copies of emails are not appearing in the Sent folder. Checking the mail account on another device or by (Outlook) webmail reveals but does not fully recover to WLM the sent emails.

More critical is the complete loss of received emails. A recently created folder had four or five important emails copied into it from a different email account. They were available in it but now Send/Receive shows only the folder with an 'Empty' message. Also:

Unable to send or receive messages for the Hotmail (name) account.

Server Error: 0x80070057
Server: 'https://m.hotmail.com/Microsoft-Server-ActiveSync'
Windows Live Mail Error ID: 0x80070057

Deleting the Hotmail account and reinstating it has failed to achieve the required result, and failures to sync as reported above are routine.

The first error code above reports something on the server. Thinking to address the second I downloaded TechUtilities which found 2,880 'issues', all of them referencing non-existent files. To fix them I was invited to register, but this was only a cover for buying something that I judge not to be needed.

How long should we wait for Microsoft to patch this up? Or just switch to Gmail?