Repair Windows Installer Service in Vista (All Versions)

For all those unfortunate souls searching and Googling for how to repair the
Windows Installer Service, I have some info for you. A couple days ago I
tried to uninstall one of my apps and stalled on an error "Windows Installer
Service cannot be accessed". After many trials and errors trying to fix this
issue, I stumbled upon a new fix for this issue that has worked in all these
situations where the Windows Installer Service will not manually start and in
essence, not allow install or uninstall tasks to complete.

Here's the easy steps:
1. Go to a Windows Vista (Any Version) computer that has the Windows
Installer service running correctly and run regedit(Start-Run-Regedit)
2. Go to the location
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\msiserver
3. Right click on this key and select "Export" and save the key to a Flash
Drive or other.
4. Run sfc /scannow on the damaged Vista computer - you won't need the
install disk as it goes to backup files on your HD. Do not reboot when
complete
5. Double click saved .reg file from working machine and import registry
settings into damaged Vista computer.
6. Now reboot and try to install/uninstall

If many of you have success with this method, please post this fix around
the WWW as I went through over 1000 links with users having the same problem
and not being able to solve it. Shame on Microsoft, very sloppy. It would
have been so nice if Microsoft released Windows Installer 4.0 as a standalone
installation with Vista's release so I could have repaired it, most users
have been doing fresh installs to fix this. Get your act together
Microsoft!!!!

I dont know other people using Vista system, most of the people i know
changed back for XP because Vist is really the worst of all systems. i want
to try with repairing windows installer, how can i do? is really there no
chance to install the windows installer service online for example?? Please
help, i cant install any programm anymore because of this!

"The CAT" suggestions worked for me. Thanks for sharing "The
CAT" .....just to add (more like subtract to be exact) one need only
run the exported reg key on the damaged machine to "fix" the
issue...no need to restart nor to run the sfc /scannow.

If you cant get your own reg key from a friend running vista, then you
could try and use the "clean reg key I used" download here:
http://www.savefile.com/files/1315653

Note the file is about very small (about 6.7 kb), I named it :123.reg

this worked great. however i do not know if this is the case for
everyone, but just encase here goes. i started with checking the
windows installer service and trying to start it and set it back to
automatic. no luck. went to google to find solution, found your post.
followed your instructions. tried to install o@o defrag again same
message. went back into services to see with your fix if i could start
the service this time, and set it back to automatic, worked. so in a
nutshell you might want to let people know the extra steps if needed
after your fix. thanks for the help. just got done reinstallking vista
and almost all of my programs and settings. was not wanting to have to
start from stratch.

I tried this solution with your "clean reg key" and the problem was not
fixed. Services shows installer is started and that it is set to
automatic. However, if i try to uninstall Adobe Reader for example I get
that message that the windows installer cannot be accessed. Will I have
to reinstall Vista Home Premium 32bit to fix this? I can install and
remove other programs I presume because they don't use the Windows
Installer.

This solution didn't work for me. I did all the steps and replaced
the
registry key, but nothing happened, i kept getting the same error.

I have the problem kinda pinpointed though: at least in my case, it's
caused by one of the windows updates - i haven't figured out which
one
yet though. My next step will be install the updates one by one to
figure out which one is messing the whole thing up, but that takes a
lot of time

The weird thing is, with so many people complaining about it, howcome
haven't they issued a report about it yet... I'm seriously thinkin
bout going back to XP

then please default to cats original post.

1. Go to a Windows Vista*(any version)* computer that has the Windows
Installer service running correctly and run
regedit*(start-run-regedit)*.
2. Go to the location
*HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\msiserver*
3. Right click on this key and select "Export" and save the key to a
Flash Drive or other.
4. Double click saved .reg file from working machine and import
registry settings into damaged Vista computer.
6. You may need to go back into services after the import and start
the Windows Installer service and set it to automatic.
7. You may need to restart the machine and then try an install or
uninstall and check that the service did start and that it is set to
automatic.

i did not try the .reg key download.
i got my copy of the key from my roommates computer.

this did not work for me
i followed all the steps and when i tryed to start the windows
installer i get the same as i did before: the service windows installer
started and stopped again some services stopps when its not in use of
some program...
srry for my bad english and i tryed to translate from norwegian hope u
can help me

[F'n Vista]

Here is a fix that I have finally found and it worked on my computer.

For the past month, I have been trying to install the 64bit edition of Itunes onto my mom's new computer. She has Vista Home Premium 64bit edition.
Everytime we tried to install itunes we would receive this error:

"The Windows installer service could not be accessed. This can occur if you are running windows in safe mode, or if windows installer is not correctly installed. Contact your support personnel for assistance"

Actually, everytime we tried to install any 64bit program we would receive this same error. I searched high and low and tried countless solutions.
Unregistering and reregistering the installer service, stopping and restarting, using the Windows installer cleanup utility, etc...none of these things helped.

Today I came across a blog "Think#Knowledge Blog" that SOLVED my problem.

This is the solution that worked for me:

Go to this registry key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSIServer

Look for
WOW64 and it's value.
Is it 0x00000001 (1) ?

This value tells Windows Installer only to deal with 32-bit installers and to return you an error whenever you try to install something that is 64-bit. To fix it, just set the value to 0. So you will see in your editor:

WOW64 REG_DWORD 0x00000000 (0)

After changing the value to zero, restart your Windows Installer Service by using services.msc or reboot.

This simple solution of changing the 1 to a 0 allowed me to finally install Itunes on Vista 64.

[Ibrehim]

hi,

Iam trying to install wnds xp sp2, besides to vista Basic wnds which is originally on my laptop Toshiba. Though I already partitioned the HDD, I couldnt install the wnds xp in my laptop. Any idea to make this happen guys?

[Rambler]

F'n Vista,
Bless ya. I've tried so many suggestions to fix my Windows Installer. Your simple(r) suggestion did the trick.