Recently, I am experiencing a puzzling problem with my email client - Windows Live Mail (WLM)

I suspected that I am not receiving some emails in my WLM Inbox, so I checked on my email Server (Heart Internet) and I can see a few perfectly valid  emails but they are not being transferred to my WLM Inbox when I click on 'Send/Receive'. I have had my account with Heart Internet fully checked but no problems were found. Out of interest, I downloaded another email client (Mailbird) and the 'missing' emails in my Heart Internet Inbox were immediately transferred to the Mailbird Inbox. So, this would tend to suggest that the problem was within the WLM client.

I deleted all the email accounts from my copy of WLM and then re-installed them from scratch, however, this did not cure the problem.. some emails (which I know are from good sources and which I have previously had email from..) still will not transfer from my Heart Internet server to my WLM Inbox.

I do not have any filters activated in WLM which would reject these emails and most emails are being transferred normally. I have tried to find any specific reason why just a few emails are not being transferred, but so far, have drawn a blank.......

I would really appreciated some help in finding a solution to this annoying problem, before I tear out what little hair I have left !!

Computer Details :

Laptop : ACER Travelmate 8G RAM

OS : Windows 10 Pro 64 bit with all updates.

OS Upgraded from Windows 7 when it was available

[Original subject: Windows Live Mail Problem]