Wrong icons displayed in Windows 10

I have the same problem as well. Rebuilding icon cache does not work either. It seems that Acrobat DC link is messed up.

Here is how I fixed it. From start menu, right click on Adobe Acrobat DC => Click More => Click Open File Location. In my case, the icon location is at C:\ProgramData\Microsoft\Windows\Start Menu\Programs (lets call this one SartMenu folder)

Select the icon, and press Delete

Fix Approach 1 If you already have a Adobe Acrobat DC link on your desktop with correct icon, you can simply copy this icon over to the StartMenu folder

Fix approach 2

Proceed to open a new Windows Explorer window and browse to C:\Program Files (x86)\Adobe\Acrobat 2015\Acrobat. Create a short cut for Acrobat.exe to the Desktop, and then follow the step in Fix Approach 1

I believe the underlying reason is the Adobe MSI installer breaks Microsoft's rules for creating a Windows installer package. Under the documentation, we read:

Icon files that are associated with shortcuts must be in the EXE binary format and must be named such that their extension matches the extension of the target.... For example, if a shortcut is to point to a resource having the key file Red.bar, then the icon file must also have the extension .bar.

(https://msdn.microsoft.com/en-us/library/windows/desktop/aa369210(v=vs.85).aspx)

In the MSI installer for Adobe Reader DC / 2015 / 2017 we see the 'Icon' table entries, all of which have the extension '.ico' by default:

If you edit the MSI with Orca and do a find/replace to change '.ico' to '.exe' on every relevant table, and then repair / reinstall the MSI, the problem does not reoccur. It would be helpful for Adobe to fix this in the MSI directly for everyone in another release.

After the hints from Minkus (which he is correct from application point of view), I dig further and found out the root cause of the wrong icon is due .ico file associated with other applications which were unable to handle the icon if the content of the .ico file is actually a .exe file, such as Windows 10 Photos app. In other words, when you double click on the .ico file, the application which was launched was unable to handle the icon (due to what Minkus mentioned).

Instead of uninstalling the application which was associated with the .ico file (which should work as well), just do the following:

1. Find yourself an .ico file, or just create one yourself by renaming a file to one with extension .ico.
2. Right click on it, then choose Open with > Choose another app.
3. Choose Paint, optionally check Always use this app to open .ico files, then click OK.

If you choose Always use this app to open .ico files, the icon should back to normal immediately. If you didn't, then you will need to reboot your PC.

This should fix most wrong icons on taskbar, desktop, shortcut, except those in Start Menu search result which I still have no idea how that can be fixed.

Try right-clicking on the taskbar and running Task Manager. In the "Processes", under the "Windows processes" section, you should find "Windows Explorer" nearly at the bottom of the list. Click on it and then click the "Restart" button. This fixed the incorrect icon in the taskbar for me.