Hi All, I'm currently unable to install any applications using Windows Installer. I've scoured the forums and tried everything suggested, but I still can't get it to work - I've turned off CEIP, ensured that the process is running correctly, unreg'd and reregistered the installer, ensured that _MachineThrottling issue wasn't the case in HKLM\Software\Microsoft\SQMClient\Windows\DisabledSessions, and run sfc /verifynow. Everything came up clean, but the installer still isn't working. Is there anything else I can try to get this working, or is a reinstall the only option? Thanks, Tim

Hi, I would like to confirm the following questions with you first: 1. What was the error message? 2. What applications failed to install? 3. Where did you get these application installation files, from the Internet or from the installation disks? 4. Can you install Windows Updates?Arthur Li - MSFT

Hi Arthur,1. The error message varies by application. Skype gives me "Installing Skype failed; code 1601. The windows installer service could not be accessed. Contact your support personnel to verify that thw Windows Installer service is properly registered." The common theme is that windows installer could not be accessed or is unregistered.2. I've thusfar had both JRE and Skype fail to install.3. Internet. Tried downloading the files multiple times to confirm they aren't corrupt.4. Just tried - no. Windows update returns Code 80070103, "Windows Update encountered an unknown error."I'm not sure where this came from - I've been running W7 and it's been stable for months. It's been a few weeks since I've tried to install any new applications, but this is the first time I've had issues.Thanks,Tim

Have you tried putting the system into cleanboot or enabling windows installer in safe mode then installing in that environment (Just for diagnostic purposes).

Hi timssopomo, In order to make sure that the downloaded installation files are good, you’d better reinstall your network card driver first. You can run services.msc to find and click Start button to start Windows Installer service. If it does not work, I suggest you repair the Windows Installer registry. Repair the registry key for Windows Installer========================1. Click Start, type REGEDIT in the Search bar, and press Enter. Note: If UAC (User Account Control) window is prompted for permission to continue, please click Continue. 2. Navigate to [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\msiserver], right click on msiserver and click Export under the File menu, choose All under Export range, select Desktop in the Save in box and type backup in File Name. Then click Save. Note: The backup file is on the Desktop and named backup.reg. We can simply restore the registry by double-clicking the backup.reg file. Once we have completed the troubleshooting and the issue has been resolved we will want to delete that file. 3. Click Start, type notepad in the Search bar and press Enter. 4. Copy the following commands and then paste them into the opened Notepad window. Windows Registry Editor Version 5.00 [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\msiserver] "DisplayName"="@%SystemRoot%\\system32\\msimsg.dll,-27" "ImagePath"=hex(2):25,00,73,00,79,00,73,00,74,00,65,00,6d,00,72,00,6f,00,6f,00,\ 74,00,25,00,5c,00,73,00,79,00,73,00,74,00,65,00,6d,00,33,00,32,00,5c,00,6d,\ 00,73,00,69,00,65,00,78,00,65,00,63,00,2e,00,65,00,78,00,65,00,20,00,2f,00,\ 56,00,00,00 "Description"="@%SystemRoot%\\system32\\msimsg.dll,-32" "ObjectName"="LocalSystem" "ErrorControl"=dword:00000001 "Start"=dword:00000003 "Type"=dword:00000010 "DependOnService"=hex(7):72,00,70,00,63,00,73,00,73,00,00,00,00,00 "ServiceSidType"=dword:00000001 "RequiredPrivileges"=hex(7):53,00,65,00,54,00,63,00,62,00,50,00,72,00,69,00,76,\ 00,69,00,6c,00,65,00,67,00,65,00,00,00,53,00,65,00,43,00,72,00,65,00,61,00,\ 74,00,65,00,50,00,61,00,67,00,65,00,66,00,69,00,6c,00,65,00,50,00,72,00,69,\ 00,76,00,69,00,6c,00,65,00,67,00,65,00,00,00,53,00,65,00,4c,00,6f,00,63,00,\ 6b,00,4d,00,65,00,6d,00,6f,00,72,00,79,00,50,00,72,00,69,00,76,00,69,00,6c,\ 00,65,00,67,00,65,00,00,00,53,00,65,00,49,00,6e,00,63,00,72,00,65,00,61,00,\ 73,00,65,00,42,00,61,00,73,00,65,00,50,00,72,00,69,00,6f,00,72,00,69,00,74,\ 00,79,00,50,00,72,00,69,00,76,00,69,00,6c,00,65,00,67,00,65,00,00,00,53,00,\ 65,00,43,00,72,00,65,00,61,00,74,00,65,00,50,00,65,00,72,00,6d,00,61,00,6e,\ 00,65,00,6e,00,74,00,50,00,72,00,69,00,76,00,69,00,6c,00,65,00,67,00,65,00,\ 00,00,53,00,65,00,41,00,75,00,64,00,69,00,74,00,50,00,72,00,69,00,76,00,69,\ 00,6c,00,65,00,67,00,65,00,00,00,53,00,65,00,53,00,65,00,63,00,75,00,72,00,\ 69,00,74,00,79,00,50,00,72,00,69,00,76,00,69,00,6c,00,65,00,67,00,65,00,00,\ 00,53,00,65,00,43,00,68,00,61,00,6e,00,67,00,65,00,4e,00,6f,00,74,00,69,00,\ 66,00,79,00,50,00,72,00,69,00,76,00,69,00,6c,00,65,00,67,00,65,00,00,00,53,\ 00,65,00,50,00,72,00,6f,00,66,00,69,00,6c,00,65,00,53,00,69,00,6e,00,67,00,\ 6c,00,65,00,50,00,72,00,6f,00,63,00,65,00,73,00,73,00,50,00,72,00,69,00,76,\ 00,69,00,6c,00,65,00,67,00,65,00,00,00,53,00,65,00,49,00,6d,00,70,00,65,00,\ 72,00,73,00,6f,00,6e,00,61,00,74,00,65,00,50,00,72,00,69,00,76,00,69,00,6c,\ 00,65,00,67,00,65,00,00,00,53,00,65,00,43,00,72,00,65,00,61,00,74,00,65,00,\ 47,00,6c,00,6f,00,62,00,61,00,6c,00,50,00,72,00,69,00,76,00,69,00,6c,00,65,\ 00,67,00,65,00,00,00,53,00,65,00,41,00,73,00,73,00,69,00,67,00,6e,00,50,00,\ 72,00,69,00,6d,00,61,00,72,00,79,00,54,00,6f,00,6b,00,65,00,6e,00,50,00,72,\ 00,69,00,76,00,69,00,6c,00,65,00,67,00,65,00,00,00,53,00,65,00,52,00,65,00,\ 73,00,74,00,6f,00,72,00,65,00,50,00,72,00,69,00,76,00,69,00,6c,00,65,00,67,\ 00,65,00,00,00,53,00,65,00,49,00,6e,00,63,00,72,00,65,00,61,00,73,00,65,00,\ 51,00,75,00,6f,00,74,00,61,00,50,00,72,00,69,00,76,00,69,00,6c,00,65,00,67,\ 00,65,00,00,00,53,00,65,00,53,00,68,00,75,00,74,00,64,00,6f,00,77,00,6e,00,\ 50,00,72,00,69,00,76,00,69,00,6c,00,65,00,67,00,65,00,00,00,53,00,65,00,54,\ 00,61,00,6b,00,65,00,4f,00,77,00,6e,00,65,00,72,00,73,00,68,00,69,00,70,00,\ 50,00,72,00,69,00,76,00,69,00,6c,00,65,00,67,00,65,00,00,00,53,00,65,00,4c,\ 00,6f,00,61,00,64,00,44,00,72,00,69,00,76,00,65,00,72,00,50,00,72,00,69,00,\ 76,00,69,00,6c,00,65,00,67,00,65,00,00,00,00,00 "FailureActions"=hex:84,03,00,00,00,00,00,00,00,00,00,00,03,00,00,00,14,00,00,\ 00,01,00,00,00,c0,d4,01,00,01,00,00,00,e0,93,04,00,00,00,00,00,00,00,00,00 5. After pasting the above commands, please click File on the menu and click Save. 6. Type in fix.reg as the file name and select to save the file on the Desktop. Click Save. 7. Go to the Desktop, double click fix.reg. A dialog box will pop-up indicating "Are you sure you want to add the information in fix.reg to the registry?". Click Yes. Note: The operation requires administrative privileges. Please click Continue when the User Account Control dialog-box appears. 8. Reboot the computer and try to start Windows Installer service again to check the issue. What’s the result? The Windows Update error code 80070103 may be not related to the Windows Installer service. This error code always happens on the hardware driver update when the driver update is not newer than the one you have installed. For your information, please check this article: Windows Update error 80070103. In fact, we cannot start Windows Installer service in Safe Mode. But it is necessary for you to test the issue in Clean Boot, if the issue persists. I also suggest you upload the following information to SkyDrive and provide us the link for analyzing. Collect the System Information ======================== 1. Click Start, type in msinfo32 in the Search bar and then press Enter. 2. Choose Save from the File menu and save it as an NFO file. 3. Find the file, right-click on this file, click Send To, and click Compressed (zipped) Folder. 4. Send the compressed file to me. Collect the WindowsUpdate.log ======================== 1. Press the Windows key and the R key at the same time, type: %windir% and press Enter. 2. Locate a file named WindowsUpdate.log and send it to us. Hope it hopes!

Hi Arthur_Li , I'm having a similar problem, could you please help me sort it out? Don't know what else to try, you seem to know about this topic. Followed your suggestions (as well as many others) with no luck. Here's my thread. Any help appreciated. If you need some extra information just ask for it, I'll provide it as soon as possible. Hope to hear from you. Thanks in advance.