The error: “This file came from another computer and might be blocked to help protect this computer”
The reason you receive this message is because Windows has detected a file came from a different computer (so, you’re receiving it for your protection). However, this Blocking, which has to be Unblocked, can be quite annoying if you have multiple blocked files. I did some research, and have listed different solutions for handling blocked files.
If the file is a compressed file
Before unzipping, click the Unblock button on the .ZIP, or .RAR, etc.
PowerShell: link
dir c:\mydir -Recurse | Unblock-File
or
Unblock-File .\MyFile.PDF
Streams from Microsoft
To recursively remove this stream for all files, follow these steps :
1. Download the Streams CLI executable from Microsoft
2. Put the streams.exe executable in your Windows directory
3. Run this line in the command line: streams -s -d directory
Adding this reg key to your registry will give you the ability to right-click and unblock
Windows Registry Editor Version 5.00
[HKEY_CLASSES_ROOT\*\shell\unblockfile]
@=”Unblock file”
[HKEY_CLASSES_ROOT\*\shell\unblockfile\command]
@=”cmd /k streams -d \”%1\””
[HKEY_CLASSES_ROOT\Directory\shell\unblockallthefiles]
@=”Unblock the files inside”
[HKEY_CLASSES_ROOT\Directory\shell\unblockallthefiles\command]
@=”cmd /k streams.exe -d -s \”%1\””
Or, for Widnows 8
Windows Registry Editor Version 5.00
[HKEY_CLASSES_ROOT\*\shell\powershell] @=”Unblock Files”
[HKEY_CLASSES_ROOT\*\shell\powershell\command] @=”C:\\\\Windows\\\\system32\\\\WindowsPowerShell\\\\v1.0\\\\powershell.exe
Unblock-File -LiteralPath ‘%L'”
Also, just for fun, check out SysInternals.
References
http://www.thewindowsclub.com/fix-windows-blocked-access-file