Install Steps:

UNINSTALL OLD NAMESPACES, PROVIDER AND WEB SERVICES
 1. Open the MPS Deployment Tool.
 2. Expand "Hosted Exchange."
 3. Expand "Exchange Provisioning."
 4. Right-click "Exchange 2007 Hosted Email" and select Uninstall.
 5. Right-click "Exchange 2007 Managed Email" and select Uninstall.
 6. Right-click "Exchange 2007 Provider" and select Uninstall.
 7. Expand "MPS Web Services."
 8. Expand "Hosted Email 2007 Web Service."
 9. Right-click each server underneath and select Uninstall.
10. Expand "Managed Email 2007 Web Service."
11. Right-click each server underneath and select Uninstall.
12. Click "Start Deployment."
13. Wait for the "Deployment Completed" message.

COPY NEW PROVIDER MSI
1. Use Windows Explorer to navigate to your MSIShare directory. If you are unsure where this is, click the File menu in the MPS Deployment Tool and choose "File Locations." Note the path for "Installer Files."
2. Copy the new HostedEmail2007NS.msi file into this location, overwriting the old file.
3. Copy the new HostedEmail2007WS.msi file into this location, overwriting the old file.
4. Copy the new ManagedEmail2007NS.msi file into this location, overwriting the old file.
5. Copy the new ManagedEmail2007WS.msi file into this location, overwriting the old file.
6. Copy the new Exchange2007Provider.msi file into this location, overwriting the old file.

INSTALL NEW NAMESPACES, PROVIDER AND WEB SERVICES
1. Open the MPS Deployment Tool.
2. Right-click "Hosted Exchange" and select "Install all in this group."
3. Right-click "MPS Web Services" and select "Install all in this group."
4. Click "Start Deployment."
5. Wait for the "Deployment Completed" message.

INITIALIZE NAMESPACES
1. Open the MPS Deployment Tool.
2. Expand "Hosted Exchange."
3. Expand "Exchange Provisioning Configuration."
4. Right-click "Initialize Hosted Email 2007" and select "Execute -> Initialize Hosted Email 2007."
5. Right-click "Initialize Managed Email 2007" and select "Execute -> Initialize Managed Email 2007."
6. Click "Start Deployment."
7. Wait for the "Deployment Completed" message.

SHUT DOWN PROVISIONING ENGINE
1. On the MPS Engine servers, open Component Services.
2. Expand "Component Services."
3. Expand "Computers."
4. Expand "My Computer."
5. Select "COM+ Applications."
6. Right-click "Provisioning Engine" and choose "Shut Down."

RESET IIS
1. On the Provisioning Web Service Servers, open a command prompt.
2. Type iisreset and hit enter.