BleepingComputer.com: Windows Mail Cannot Open

Hello,
I am having problems opening Windows Mail. Whenever I try to run the program, the following error immediately pops up:

"Windows Mail can't be opened. A software restriction policy is preventing Windows Mail from opening. Contact your system administrator for more information"

As far as I know it only occurs with this program.

All user accounts are affected, not just mine.

Since I have Vista Home Premium, I don't have the Group Policy Editor, so I'm stuck as to what to do next.

Any thoughts?

Can you launch the program as administrator? There could be an issue with the program itself, can you use other mail clients like Windows Live Mail or Thunderbird?

It's only a Windows Mail issue. I've tried running as Administrator on every account. I even tried the built-in administrator account. No dice.

However, I started to look around in the registry and saw this:

HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows Mail
In this key it had the following DWORD value:

ManualLaunchAllowed and had a value of 0.

Thinking 0 means "False" and 1 means "True" I changed the value to 1...and....PRESTO! Windows Mail now works!

The funny thing, is that I was able to lauch Windows Mail before but then switched to Outlook. I needed to open Windows Mail to export my contacts and that's when I discovered the problem. I never changed anything!! What happened?

Anyways it's fixed now.