How to disable write access and only allowing read access to usb devices?

To resolve this problem, you must make the following changes to the Windows registry.

This will prevent users from writing to USB devices. If an user would like writing to USB devices, will appear a message error such as:

Unable to ......
The media is write protected.


CAUTION: We strongly recommend that you back up the registry before you make any changes to it. Incorrect changes to the registry can result in permanent data loss or corrupted files. Modify only the keys that are specified. Read the document How to make a backup of the Windows registry for instructions.

Step 1

Click on START > RUN and type regedit
Then click on Ok button.

The Registry Editor, will be appeared.
In the left pane of the Registry Editor, navigate to the following subkey (making double click on each registry key):

HKEY_LOCAL_MACHINE
SYSTEM
CurrentControlSet
Control
StorageDevicePolicies

Important: if the StorageDevicePolicies key wasn't found, in the left pane of the Registry Editor, right click on the Control key and choose NEW > Key to create a new key.
Name it StorageDevicePolicies
Now, make double click on it.

Step 2

Now, in the right pane of the Registry Editor locate and make double click on the following registry subkey named WriteProtect

If not, make it. In this case, in the right pane of the Registry Editor, right click in the white space and choose NEW > DWORD Value to create a new subkey.
Name it WriteProtect
Now, make double click on it.

Step 3

A new window will be appeared.
Modify the value in the field named Value data.
Set the value data for this subkey to:
0 (read ZERO) enable Write and Read access to USB devices;
1 (read ONE) disable Write access and only allow Read access to USB devices.

Then click on Ok button.

Exit the Registry Editor.

Restart the computer.

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See also

Disable removable USB storage devices