During Installation of Exchange 2010 you faced with "A Restart from a Previous Installation is Pending "

This note I had it when I stuck during the installation of exchange till I found this technet, the link at the bottom.
Microsoft Exchange Server setup cannot continue because a restart from a previous installation or update is pending.
The Exchange Server Analyzer reads the following registry key to determine whether a system restart is required after installation or removal of a software update such as a security update, critical update, or hotfix.
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Updates\UpdateExeVolatile
The Exchange Analyzer also checks the following registry key to determine whether a previous software update installation was not completed and the system must be restarted to finish the installation.
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\PendingFileRenameOperations

The Exchange Analyzer displays an error message if one of the following conditions is true:.
The value of the UpdateExeVolatile registry key is anything other than 0.
The PendingFileRenameOperations registry key has any value.
This error indicates that a restart from a previous install or update is pending and the system must be restarted before Exchange Setup can continue.

To resolve this issue, restart the system and then run Exchange setup again.
If the Exchange Analyzer is still reporting this error after a system restart, the registry keys may contain orphaned values that must be removed. Possible values for these keys are listed below.

To remove an orphaned UpdateExeVolatile registry key value

• Open a registry editor, such as Regedit.exe or Regedt32.exe. 
• Navigate to HKLM\SOFTWARE\Microsoft\Updates\ 
• In the right navigation pane, double-click the UpdateExeVolatile key. 
• Configure the key with a value of 0 
• Close Registry Editor. 

To delete the orphaned PendingFileRenameOperations registry key 

• Open a registry editor, such as Regedit.exe or Regedt32.exe. 
• Navigate to HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\ 
• In the right navigation pane, right-click the PendingFileRenameOperations key and select Delete. 
• Close Registry Editor. 
• Before you edit the registry, and for information about how to edit the registry, see Microsoft Knowledge Base article 256986, Description of the Microsoft Windows Registry. 

Pasted from <http://technet.microsoft.com/en-us/library/cc164360(EXCHG.80).aspx>