Q: unknown error occurred (-42110)

Removing the SC Info folder as per the "Error 3001," "-42110," or "5103" section in the Specific Conditions and Alert Messages: (Mac OS X / Windows) section of the following document seems to help most folks reporting the iTunes launch 42110s:

iTunes: Advanced iTunes Store troubleshooting

Try this... Close iTunes then Right click on the shortcut that you launch iTunes from and choose 'Properties' from the context menu. Select the compatibility tab and place a check mark in "run as administrator" and apply the settings.

Now double click the icon and relaunch iTunes - you will get a windows UAC warning on startup from windows but the error -42110 should now be resolved. You can turn off UAC warnings but that is a separate issue and answers for that can be googled.

THIS IS THE ONE THANKS BUDDY

This has helped me tremendously....I called the tech support for iTunes and they could not resolve this problem.  Amazing, thank you so much.

KGriff - That obvious, and worked like a charm. Thank you! 

Thanks, it worked!

Thank You i needed Some Help and this helped big time .

It Worked !

KGriff- Thank you! I have been looking into this error for about three weeks, unloaded, this, re-loaded that, etc. Your simple solution has my iTunes loading without the delay and error now. Thank you every much!!

Just happened to me on windows 10. Kgriff your a Savior tyvm for the help your bad a@@!