Here's how to share files in Windows 10:
Step 1: Find the file you want to share
Open up the File Explorer and navigate to the file or files you want to share. You can share any file type, although you cannot share any file type with any app. (For example, you can't share DLL files to Facebook -- I tried). Select the file you want to share by clicking on it.
Step 2: Open the Sharing menu
While there is a one-click Share button in the File Explorer, it's actually hidden inside the Sharing menu. Click Share to open up the sharing menu. Depending on what type of file you have selected, different options in the Sharing menu will be available to you. For example, if you've selected a folder, and not a file, the Share button will be grayed out and the Zip button will be available. From the Sharing menu, you can also zip, burn, print and fax files, as well as modify network sharing options.
Step 3: Click the Share button
The Share button has the same three-dot-circle icon as the Windows 8 Share charm. Click the Share button to open up the Share sidebar.
Step 4: Choose the program you want to share with
In the Share sidebar, you'll see a list of apps you can share your file with. Again, depending on the file type you're trying to share, some apps may not show up. Facebook and Twitter will not show up if you're trying to share a zipped folder, but Mail will.
Step 5: Configure your Sharing options
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