
Again, this could be due to Windows not being able to find a digital signature. Various Windows security features may prevent iTunes from installing.Without this signature, the Windows system isn’t able to verify the authenticity of the iTunes installation so it simply won’t install it.

While installing an iTunes update, the computer might not detect an iTunes digital signature.Older versions of the Windows operating system, including Windows XP, don’t support the latest versions of iTunes.Some of the top reasons can be found below. After browsing the Apple forums and finding out other users’ experience with the signature error, we got to work. By finding out what was causing the error in the first place, we’ve been able to assemble an effective list of possible fixes.

The first thing we did was investigate the error. Fix #3 – Changing Windows Security Settings What Causes iTunes Has an Invalid Signature?
