Software Deployment

Where 2 is the error and 3 is the setup trying to install.
The error (2) is most often reported as 1632 ("The Temp folder is either full or inaccessible. Verify that the Temp folder exists and that you can write to it.")
This error may occur if there are insufficient privileges on the %windir%\Installer folder, or the inability of the Windows Installer service to create the %windir%\Installer folder.
NOTE: This behavior can also occur if you have only Read permissions to the Winnt folder. This condition prevents the Installer folder from being created by Setup.
If installing from a mapped drive letter in a terminal services session: "Windows 2000 and earlier operating systems do not support passing mapped drive letter information between terminal server sessions. Since Windows Installer service runs as a service in the console session, mapped drive letters established in remote sessions are not visible to Windows Installer service, resulting in this error. This only applies when running the service in Application Server mode, not Remote Admin mode."
Note that this limitation no longer exists in Windows XP and later operating systems.
For "Internal Error 2755: Please contact product support for assistance" see Microsoft knowledge base article 251274 for a solution/hotfix.
One member offers, "I ran across this when attempting to install using an MSI which had been encrypted using EFS. I'm guessing msiexec uses an account which cannot access my encrypted files. Decrypting the file resolved this error."