Wrong Item Tooltip

[Snared]

I know absolutely nothing about Win10, but let's diagnose this for future problems on this shitty 200% privacy intruding OS since this may be interesting.

Eh, it's not that "privacy intruding" if you disable all the "privacy intruding" features.

Where's your 1.12.1 folder located?
Is there a WDB folder in that folder? Does it have itemcache inside of it?
Are you running WoW.exe as an administrator or have "Always run as administrator" ticked when you right click WoW.exe > Properties > Compatibility (tab)?

1.12.1 folder is on my G:\ drive. Yes there is a WDB folder in there with itemcache, a new one because I deleted the old one.
Yes I'm running WoW as administrator.

Start => Run => "regedit"
Under HKEY_USERS, one of the ID's will be suffixed with _Classes. One of them will contain "VirtualStore" -- find the one with VirtualStore\MACHINE\SOFTWARE\Blizzard Entertainment - you should see the path of the VirtualStore directory if you are not running WoW.exe as an administrator. If you run it as an administrator, your UI will be fucked and your SavedVariables will be with it since we need to copy your WTF folder over to your normal WoW 1.12.1 folder to not lose everything when you run WoW as an administrator.

Path in regedit should be something like HKEY_USERS\S-1-5-21-1234567890123-234923491-4328421-2202_Classes\VirtualStore\MACHINE\SOFTWARE\Blizzard Entertainment

Going to bed. Work in a few hours. I'll try to answer in the morning before work.

Here's the only path tree I found under virtual store in regedit:

[Aunstic]

Alright you've given me a lot of answers then. I stopped at the first layer: your addons. Have you disabled all your addons to see if the tooltip has changed somehow? I don't know if there's any addons that cache items before WDB or vise versa, but it's worth a shot.

As for your VirtualStore path in regedit, there should be multiple SIDs after HKEY_USERS, have you looked through all of them?

Does Win10 have some sort of symlink with drives that could cause an error? Is this a partition created from the existing Windows partition or is this a separate HDD/SSD/Flash drive?

I'm grasping at straws here. Right click your WoW folder and tell me if its read-only.