Error: "A problem occurred while trying to open this message" when opening a message on Windows Live Mail

Hi MarzenaNowak,

Welcome to Microsoft Community forum and I am here to assist you in opening your emails on Windows Live Mail. Please be informed that the error message you have receive is a generic one which means that there is not enough memory that is why you cannot open the email. To troubleshoot this, follow the steps below:

1. Restart the computer (this is to ensure that Live Mail is fully shut down, and that none of it's components are in use when the computer starts)

2. Click Start, type CMD but do not press enter

3. You will see cmd.exe in the search results, right click on it and select Run as Administrator - type your admin password if asked, and if UAC pops up asking premission, allow it

4. You should now see the command prompt, with the following displayed:

Microsoft Windows [Version 6.1.7600]

Copyright (c) 2009 Microsoft Corporation. All rights reserved.

C:\Windows\system32>

5. Copy the following (Ctrl+C)

esentutl.exe -d "%userprofile%\AppData\Local\Microsoft\Windows Live Mail\Mail.MSMessageStore"

Note: the "" are necessary

6. Right click in the command prompt Window, and select Paste, so you now see the following:

Microsoft Windows [Version 6.1.7600]

Copyright (c) 2009 Microsoft Corporation. All rights reserved.

C:\Windows\system32>esentutl.exe -d "%userprofile%\AppData\Local\Microsoft\Windows Live Mail\Mail.MSMessageStore"

7. Press Enter. esentutl will now defragment the Live Mail database file

8. Once done, you can close the command prompt, and restart the PC again

Let us know if this does not resolve your issue so we can continue our support.

Thank you.

0x800C0155,2

This happens to almost everyone who tries the defragmentation routine. The problem is this: esentutl makes a copy of the index file (Mail.MSMessageStore) and tries to defragment it. If the process is successful, the defragmented file is copied back to where it originally came from - but its owner has changed, because it was the System user account that created the file while the procedure is being run by administrator. So the normal user account doesn't have permissions to write to this file, which causes the error you're seeing. To correct this,

1. Log on to Windows with an administrator account and ensure that no programs are running.
   
2. Use Explorer to navigate to your store folder, probably at
   C:\Users\{user}\AppData\Local\Microsoft\Windows Live Mail
   where {user} is the Windows user having the problem.
   
   
3. Right-click on Mail.MSMessageStore and select Properties.
   
   
4. On the Security tab, click Advanced, then open the Owner tab.
   If the Current owner box doesn't contain your normal Windows user account, click Edit then Other users or groups.
   Type the name of your normal Windows user account into the Enter the object name... box and click Check names. The official name of the account should appear in the format {computer name}\{username}.
   
   Click OK, select this username in the Change owner to box then OK.
   
   
5. Open the Permissions tab and click Change permissions.
   

6. Click Add and type the name of your normal Windows user account into the Enter the object name... box and click Check names. The official name of the account should appear in the format {computer name}\{username}.
   
   Click OK, select this username in the Permissions box and click Edit.
   
   Select the checkbox labelled Full control in the Allow column.
   
7. Click OK three times to close all dialogue boxes.
   

8. Launch Windows Live Mail.

If you get stuck anywhere, Cancel your way out and report back.