Restore the Confirmation Prompt when Opening Multiple Mail Messages in Windows Mail and OE

When you select more than 10 messages and press ENTER to open them simultaneously in Windows Mail or Outlook Express, you’ll be prompted with the following message:
Opening all selected messages could take a few minutes.Select OK to continue.
Clicking OK will open the selected mails at a time. If you choose the Don’t show me this again option, the preference is saved in the registy and there is no GUI option to reverse the setting. Here is how to restore the confirmation prompt if you’ve accidentally disabled it.
WINDOWS MAIL

1. Click Start, Run and type regedit.exe. Press ENTER
2. Navigate to the following branch:
HKEY_CURRENT_USER \ Software \ Microsoft \ Windows Mail \ Dont Show Dialogs
3. Delete the value Open Messages Warning in the right pane.
4. Exit the Registry Editor.

OUTLOOK EXPRESS
1. Click Start, Run and type regedit.exe. Press ENTER
2. Navigate to the following branch:
HKEY_CURRENT_USER \ Identities \ {GUID} \ Software \ Microsoft \ Outlook Express \ 5.0 \ Dont Show Dialogs
Where the GUID placeholder above represents the unique identifier for your identity in Outlook Express. Each identity has a unique GUID string, looks something like this:
{D84D1456-EA50-47D6-84EF-BD4426DD0A40}
{FC8D1451-E15C-B2C1-ADEF-AC4526D10A85}
If you have multiple identities in Outlook Express, to know the GUID applicable for your identity, select each GUID and read the Username field in the right pane in the Registry Editor.
3. Select the Dont Show Dialogs branch
4. Delete the value Open Messages Warning in the right pane.
5. Exit the Registry Editor.