Several Windows 10 users are reportedly encountering iTunes syncing issues with iOS devices following the upgrade, due to some incorrect permission issues, wherein the iTunes folder becomes 'Read Only'.
It is ascertained that an inherent bug in Windows 10 update is making the iTunes folder as Read Only, which prevents your computer from syncing with the device you have connected to it.
Consequently, users who are forcing the data syncing process between their computer and iOS device via iTunes are seeing the error code -54.
Nevertheless, folks at Windows Central have identified a simple fix to resolve this issue with due credit to a tipster named Darran, who has discovered this fix.
Steps to fix error code -54 in iTunes on Windows 10
Step 1: Open Windows Explorer
Step 2: Head to the Music folder
Step 3: Right click on your iTunes folder
Step 4: Go to Properties and uncheck the Read Only option under Atrributes
Step 5: A pop-up window should now appear after the changes are applied to all the sub-folders within iTunes folder.
Step 6: if the issue persists, just ensure that you have full control on the iTunes folder: Right-click on the iTunes folder again > select properties > security and click edit > full control and then click apply.
That's it. You should now be able to sync your iOS device to your computer via iTunes without further hassles.
[Source: Windows Central]