In Windows 10 you can Move Location of Pictures Folder in Windows 10. You may have done this, for example, because your C: drive is an SSD with limited free space and you want to keep your Pictures on a larger E: drive.
When you make this move the original C:\Users\<YourUsername>\Pictures folder will be deleted. If you change your mind and want to move Pictures back to the C: drive you will have to create a new Pictures folder in your User folder and select that as the destination. If you fail to take this step and just select C:\Users\<YourUsername> then Windows warns you that you are trying to merge Pictures with you Profile and that this is a permanent change that cannot be undone.
At this point you should have cancelled, created a new Pictures folder and selected that. Unfortunately it's all to easy to click Yes before you've fully reading the warning.
The consequences of merging the folders can be very confusing, so first a description of some strange effects you may see so that you can identify this as being your problem. In the screenshots that follow a user with the name Owner has merged their Pictures folder with their user profile folder, C:\Users\Owner. The most obvious anomaly is that the user folder now appears in some parts of File Explorer under the name Pictures and with a 'pictures' icon, but a Command Prompt will still show its true name.
Your User folder will also contain a Pictures folder which, if you click on it, will take you to your same User folder, but with some subtle differences in what you can see there. You won't see a Pictures folder any more, but you will now see Camera Roll and Saved Pictures.
Windows is correct in saying that you cannot undo the redirection with the normal tools Windows provides. But it is possible to manually separate the Pictures and Profile functions of the merged folder. To repair the damage done, follow these steps. It's important to perform all the steps in this order, so do not try any shortcuts.
Here's How:
1. Open File Explorer, in the View ribbon tick 'File name extensions' and 'Hidden files'. On the View ribbon, click Options > change folder and search options. In the window that opens click the View tab. Scroll down and untick 'Hide folder merge conflicts' and 'Hide protected operating system files'. Click Apply or OK to save these changes.
2. In the left hand column of file Explorer (otherwise known as the Navigation Pane) click on your User folder (the one with a user icon to its left). In these examples the user has the name Owner.
3. In your user folder, create a new folder named Pictures. You will now see two Pictures folders, the original one with a pictures icon, the new one as a plain folder.
4. find the desktop.ini file in C:\Users\<yourname> and move it into the new C:\Users\<yourname>\Pictures you just created.
5. Using File Explore to cut and paste, move your live folders 'Camera Roll', 'Saved Pictures', and 'Screenshots' if it exists (will only be there if you've used WinKey+PrtScn) and any photos to the new C:\Users\<yourname>\Pictures you created.
6. Open Registry Editor (regedit) and go to the key...
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders
Before making any registry changes, always back up the registry key in case you make an error and need to restore it. Select the key (in this case User Shell Folders) in the left hand list, then use File > Export... to save the key as a .reg file. You can restore the key by double-clicking on the .reg file you created.
7. You can now edit both {0DDD015D-B06C-45D5-8C4C-F59713854639} and My Pictures to point to %USERPROFILE%\Pictures
Double-click on the item in the right hand list to open the edit dialog box, type the changes and click OK to save them. Sign out and then back in, or restart the PC for these registry changes to take effect.
That's it. You now have a functional pictures folder with all its standard sub-folders located in the C:\Users\<yourname>\Pictures folder. If you wish, you can now move it elsewhere. Or you can just leave it where it is.
NoteInitially your new Pictures folder may just have a plain folder icon. After making the changes it took about 10 minutes of using the PC before the normal pictures folder icon returned. If it doesn't return, try a Restart or two. If it still doesn't come back try rebuilding the Icon Cache.
my thanks go to @Barman58 for bringing desktop.ini to my attention, moving that was key to getting this to work.