Question about Outlook Express

Since around 1pm all emails to my domain have been bounced undelivered with the following message:

"Final-Recipient: rfc822; *** Email address is removed for privacy ***
Action: failed
Status: 5.0.0
Remote-MTA: dns; ci-ni.org.uk (50.115.23.71, the server for the domain.)
Diagnostic-Code: smtp; 550-The mail server could not deliver mail to *** Email address is removed for privacy ***.  The account
 550-or domain may not exist, they may be blacklisted, or missing the proper dns
 550 entries.
Last-Attempt-Date: Wed, 25 Jul 2018 05:36:48 -0700 (PDT)"

Can you help me fix this issue? Many thanks,

Roger

Have been using windows live mail for a long time. On Windows 10

Windows Live Mail 2012

Version 2012 (Build 16.4.3528.0331)
Copyright © 2012 Microsoft Corporation. All rights reserved.

Recently have been getting

The contents of this message cannot be found.

Intermittent thru my mail. The mail is fine on the server but every day I get at least one with this message.

The messages are from my usual websites and users so not really sure why this is happening and only recently.

Stared approx 10th of June and 1 or everyday since then.

My husband is on an older version with win7 and having no problems.

I tried searching for similar questions but couldn't find one that truly answered my questions. I imported several messages that I had previously exported with WLM 2012. The process I used was as follows

• I imported a few of the exported folders. Since there were over 20, I didn't want to try to do them all at once.
  
• Next, I opened each email folder in WLM under the imported folder and moved the emails into new local folders I created under each of my email accounts.
• Once the imported mail folders were empty, I deleted them from the imported folder in WLM.
• I then closed WLM down to allow it to completely close its databases.
• After reopening WLM, I imported some more emails, but instead of them going into the original Imported folder, there was now an Imported Folder(1) in WLM, and the newly imported email folders were under that folder. I repeated the process of moving the imported emails into local folders. This time, in addition to deleting the imported folders, I also deleted Imported Folder(1). After exiting WLM, I went into Windows Explorer and looked at the file structure for Windows Live Mail under C:\Users\Tom\AppData\Local\Microsoft\Windows Live Mail. I still see the Imported Folder and Imported Folder(1), even though the Imported folder(1) is no longer visible from within WLM.

Is there a way to clean up this file structure? I am hesitant to mess with this from Windows Explorer, but it doesn't appear that WLM is going to clean this up on its own, even when I forced it to compress its database by changing "Compact the database on shutdown every 2 runs". I got the message "Recovering unused storage" so I know WLM compacted the database.  I am concerned that future imports will continue to create additional Imported Folders and that this might cause problems other than the cosmetics of the Explorer file structure.

My Windows Live Mail abruptly stopped opening.  When attempting to open from the shortcut the message reads:

             C:Windows\System32\MSVCR110.dII is either not designed to run on Windows or it contains an error.  Try installing the program again using the               original installation media or contact your system administrator or the software vendor for support.  Error status 0xc000012f.

I cannot access saved emails, inbox, outbox and mos important, address book.  Any help available?  I have the settings to set the account backup but there is no longer a download available.