“Error 1719. The Windows Installer service could not be accessed”
If you try to add or remove a program that uses Windows Installer Microsoft Software Installation (MSI) package file (.msi), you may have seen the following error.
I ran into this when I was trying to remove Microsoft AntiSpyware Beta 1 software from Add or Remove Programs in Windows XP. You may experience this error with Microsoft Office or any other software that uses .msi to install a program. The reason for the error is typically corrupted or missing Windows Installer files on your computer. There are a couple of solutions to fix the problem. You can either try to re-register (Plan A) or re-install (Plan B) the Windows Installer.
Plan A
To re-register Windows Installer, first locate the Msiexec.exe file on your computer (typically in C:\Windows\System32) and then verify in the registry that the location is pointing to the correct path. Run regedit.exe and go to this location: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSIServer. Double-click on the ImagePath entry in the right-hand pane and make sure it matches with the actual path for Msiexec.exe, if not correct the path. Typically the enry would look like this: C:\Windows\System32\Msiexec.exe /V. Reboot your computer into Safe Mode and at the command prompt run msiexec /regserver to re-register the Windows Installer and then reboot your computer in normal mode.
Plan B
If Plan A doesn’t fix the problem then try re-installing the Windows Installer. Reboot in Safe Mode, rename the following three files and then reboot your computer.
msi.dll
msiexec.exe
msihnd.dll
Windows XP already includes Windows Installer version 2.0. Reboot your computer in the normal mode. For more information on this topic, check out Microsoft’s KB article Q315346.