When you download a file from the internet, Windows operating system automatically adds an alternate data stream (ADS) to that file to identify it as a foreign file that must be handled with extra care. This newly added ADS is called “Zone.Identifier” and has a small content “[ZoneTransfer] ZoneId=3”. Using this extra data, Windows can tell that this file came from the internet. Every time you access such a file, Windows may show a warning message indicating that since you downloaded this file, it could be harmful and that you should take extra precaution.
Typically, you can remove this Zone.Identifier ADS from the File Explorer easily. For this, you can right-click on the file, select Properties and then click on the Unblock File button. This method is very easy but you have to use it on each of the files separately – one by one. This can take a long time if you have to unblock multiple files.
If you want to unblock multiple files (clear the Zone.Identifier stream from a large number of files) then you can make use of the Unblock-File PowerShell cmdlet. Here is how:
- Open the folder files of which you want to unblock (clear the Zone.Identifier stream).
- Click on the File and then select Open Windows PowerShell Open Windows PowerShell.
- In the PowerShell prompt, type dir .\* | Unblock-File
This will clear the Zone.Identifier from all the files in that folder. You can also use the wildcards to limit the filenames to a certain number of files. For example, in order to process only the EXE files, you can give the command dir .\*.exe | Unblock-File which will then clear the Zone.Identifier stream from the EXE files only. This method does not require administrator level access until the files being accessed are accessible only to the administrator level user.
If you want to add the Zone.Identifier stream back into any file, then you can use our small utility AlternateDataSteam. For the stream name use Zone.Identifier and for data [ZoneTransfer] ZoneId=3 should be used.