You may encounter an error stating that Windows Installer is not available in Windows 7 iTunes. Well, there are several steps you can take to fix this problem. So we’ll get to it now. When installing another program, I received the error “Unable to access the Windows Installer service”, but the update should be the same. … Run% windir% syswow64 msiexec.exe / unregister. Run% windir% syswow64 msiexec.exe / regserver. Close Command Prompt and restart.
When installing or updating iTunes for Windows on 64-bit Windows Vista or Windows 7, the message “Unable to access Windows Installer Service” appears as shown in the following screenshot:
Other 64-bit installers will not be installed either, but 32-bit installers will be installed on the system.
You can set a registry key on your system to disable 64-bit installations.
Note. The following instructions are for editing the registry. Please back up your registry before proceeding.
(1) Run Regedit as administrator. In the Start Search box, type regedit. Right click on the regedit entry and select “Run as administrator” as shown in the following screenshot:
(2) In the left pane of Regedit, click the triangle next to HKEY_LOCAL_MACHINE to expand its contents.
(3) Expand SYSTEM content
(4) Expand the contents of the CurrentControlSet
(5) Expand the content of the services
(6) Select MSIServer
(7) Check in the right pane of Regedit if there is anyReading WOW64 REG_DWORD 0x00000001 (1) as per the following screenshot:
(8) If this value is present, right click on WOW64 and select “Change” according to the following screenshot:
(9) On the “Edit DWORD (32-bit)” screen that opens, replace the 1 in the Data Value field with 0 (zero) as shown in the following screenshot:
(10) Click OK. The WOW64 REG_DWORD value should now be 0x00000000 (0) as shown in the following screenshot:
(11) Close regedit.
(12) Restart your computer.
Now try installing or updating iTunes for Windows again.
Reasons Why Windows Installer Is Not Working
Windows Installer is a Microsoft Windows component used to install, maintain, and remove software. So how do you fix the unavailable Windows Installer service or fix the problem with the not working Windows Installer?
Here are the main reasons for this error and you can find the best solution for this problem:
- Windows Installer is not installed correctly.
- Windows Installer files are damagedexpected or absent.
- Registration Permissions or.
- Windows Installer is out of date or has a compatible issue.
Don’t worry if you run into this problem on your computer. Try the methods presented in the next part to get Windows Installer to work correctly again on Windows 10/8/7.
Right-click the installer you downloaded in step 3 — it’s called iTunesSetup or iTunes6464Setup — and choose Run as Administrator.
If you have already installed iTunes, the installer will ask you to repair the software.
After the recovery is complete, restart your computer and launch iTunes.