I keep getting errors installing 7.20.2 and can't uninstall 7.16.2. Tried restarting in uninstalling + installing 7.20.2. No luck. I also deleted the Boinc dir and tried to install, and uninstall for good measure. I also have Oracle VB installed but it's not running.n

I'm using a 11th Gen Intel i5.

The windows error (when trying to remove or install):
"Error 1719. Windows Installer service could not be accessed..."

Any suggestions?

You may have trouble with the Windows Installer service itself. So do check that the Windows Installer service is running:

1. Press Winkey + R and type services.msc then press Enter.
2. Right-click the Windows Installer service and choose Properties.
3. If the Startup type box is set to Disabled, set it Manual.
4. Click OK to close the properties window.
5. Right-click the Windows Installer service and choose Start.

Lastly, it can be that the Windows Installer service is broken, and needs to be re-registered.
Press Windows Search, type cmd, right-click on the found Command Prompt app and choose to Run as an Administrator.
Next type the following commands into the command prompt window, each followed by a press on Enter:

%windir%\system32\msiexec.exe /unregister
%windir%\system32\msiexec.exe /regserver
%windir%\syswow64\msiexec.exe /unregister
%windir%\syswow64\msiexec.exe /regserver

After having done that, reboot the computer. And try to install again.

Thanks Jord. Same error after completing all the steps including reboot. Neither uninstall or install are working.

Do you run an updated antivirus on that system, or have you otherwise run Windows Defender on it (active scan)?
If that's not running and you can't get it to run either (same thing, service not available), you may be infected with something. In that case go to https://www.eset.com/int/support/sysrescue/ and get one of its live rescue scan options and run that.

I have the same problem with Win 11 Pro. I've done services, unregistered and re-registered. I have an active Bitdefender account, Malwarebytes and super Antispyware. No luck installing. Using AMD 5800 with 16 gb 3600 ram

That 2 of us are having the same challenge suggests to me a possible installer or other issue w 7.16 and/or 7.2 and/or Win 11, but that's purely a guess of course.

Can either of you install anything else without problems? Like Notepad++ for instance?

Have either of you tried:
1. Go to Windows Search, type cmd, right-click on the Command Line app and choose "Run as administrator".
2. In the command line window, type sfc /scannow and hit Enter.
3. Wait for that to finish... check if you got rid of the error...
4. In the same command line window, type DISM.exe /Online /Cleanup-image /Restorehealth and hit Enter.
5. Wait for that to finish... check if you got rid of the error...

Via Regedit:
1. Press Windows Key + R buttons, type regedit and open it up.
2. On the left pane, navigate through this path HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\msiserver
3. After clicking on msiserver, move your eyes onto the right side and look for the key named WOW64
4. If there is no such available, right-click on blank space and choose New > DWORD (32) to create a new value. Name it WOW64
5. Finally, open WOW64 and set its Value data to 0, in case it doesn’t have it yet.
6. Also make sure Base is set to Hexadecimal.
7. Click OK to close the window and check if you got rid of the error eventually.

Via a known good Restore point:
1. Select the Start button, then type control panel in the search box next to the Start button on the taskbar and select Control Panel (Desktop app) from the results.
2. Search Control Panel for Recovery, and select Recovery > Open System Restore > Next.
3. Choose the restore point related to the problematic app, driver, or update, and then select Next > Finish.

Thanks Jord. I tried the first set and restarted, and still no success uninstalling or installing.

Still no luck. Other programs, like Malwarebytes installs with mo problems.

Thanks. I've written a Github issue about it. (#4883)
Can you two in the meantime tell me which Windows 11 versions you run?

All you need to do is open the Settings app, which will launch into the System section by default. Scroll down to find the About option and click it. You'll see all the information about Windows 11 under Windows specifications, including the edition, version, and build number.

From the developer:

I was not able to reproduce this on clean WIn11 21H2 (Build 22000.739) installation.
I need some additional information:

- is this an issue with regular installer or installer with VBox?
- does this happen when installing BOINC by default or as a service?

I remember I saw similar issue when some other installations stucks and there was some processes like 'msiexec.exe' running that were not related to BOINC installer.

So please before running BOINC installation check that no other 'msiexec.exe' instances are running in Task Manager:

I've just upgraded from v7.16.20 to v7.20.2 under Windows 11 Pro, with no problems - so this isn't universal.

Another question occurs to me: are these machines each your own personal property, free of any restrictions? Or were they supplied by an employer or educational establishment, and possibly subject to group policy restrictions when used on the establishment's network?

Edition Windows 11 Pro
Version 22H2
Installed on ‎5/‎12/‎2022
OS build 22622.575
Experience Windows Feature Experience Pack 1000.22634.1000.0

This machine is personal property

Windows Feature Experience Pack

So in essence you are running beta Windows. Have you reported this behaviour to Microsoft?

I have the Feature Experience Pack, too - but an earlier version, 1000.22000.856.0

I'm not on any Beta or Insider program, and my main version is 21H2. I've just run a manual update, and I've got nothing new offered from that - just an anti-virus definition update for Microsoft Defender.

Ah, I did check that (and see I have it on Windows 10 as well) and it seems it's Microsoft's way of "including features critical to Windows functionality." So they could've added something that breaks older Microsoft Installer's functionality. Can you update to the version that Mycque is on?

I'll do it as soon as it's offered, but I don't want to break BOINC too badly just yet. I've got some accuracy/validation testing to do for Bernd at Einstein, and I need to do it on that particular CPU - just waiting for the cooler weather. I'll fire that up now, and maybe try the 'Insider' pathway at the weekend if we haven't got to the bottom of this by then.

The rain has arrived here, should I shoo some over your way?

The rain has arrived here, should I shoo some over your way?

Yes please! Allotment is desperate for it!

{O/T} Looks like some will come tomorrow, to the Midlands and above that.