Různé návody jak opravit instalační službu ve Windows.

Instalační služba 4.5 pro Windows XP, Server 2003, Vista, Server 2008 X86, X64
https://www.microsoft.com/cs-cz/download/details.aspx?id=8483

https://msdn.microsoft.com/cs-cz/library/windows/desktop/dd408114(v=vs.85).aspx

https://support.microsoft.com/cs-cz/kb/2642495

https://msdn.microsoft.com/en-us/library/windows/desktop/aa372856(v=vs.85).aspx

https://support.microsoft.com/cs-cz/kb/942288

https://social.msdn.microsoft.com/Forums/windows/en-US/c3f91eac-d880-41fa-b86d-5568d4ead02f/how-to-download-windows-installer-50-?forum=winformssetup

https://msdn.microsoft.com/en-us/library/windows/desktop/cc185688(v=vs.85).aspx

http://superuser.com/questions/699703/repairing-windows-installer-on-windows-7

https://support.microsoft.com/cs-cz/kb/2438651

http://answers.microsoft.com/en-us/windows/forum/windows_7-performance/need-to-reinstall-windows-installer-in-windows-7/4cb8e54c-5a4e-439d-9d46-1dcd387d2604?auth=1

Pomalá instalace aplikací
https://social.technet.microsoft.com/Forums/windows/en-US/e3d8dfbf-6011-43ab-a0a4-384f93d53c5a/windows-installer-working-very-slow-solved?forum=w7itproperf