This could potentially go under Windows as well, but I will leave it here for now as it's the iTunes application which is causing this. I've just had my iTunes perform an update to 12.3 and it's now no longer working. Showing an error message saying the following;
"iTunes was not installed correctly. Please reinstall iTunes
Error 7 (Windows error 5)"
I'm using Windows 10 Pro 64bit. I've had a look online and there's actually not too much out there regarding this error message. I've tried the following steps to troubleshoot;
- Clean the registry (using CCleaner)
- Ensure no 3rd party AV is stopping it from installing (only using Windows Defender)
- Ensured .NET is up to date
The odd thing is even after I've completely removed iTunes and restarted etc, after downloading again and installing, I get the same error message.