Thank you for choosing Microsoft Community!
As per the issue description, you are unable to open Device Manager.
Please reply to these questions, to understand the issue better and help you further:
1. Do you receive any other performance issues on the computer?
2. Have you made any changes to the computer prior to the issue?
This issue may occur when one or more of the .dll files that are used by the Microsoft Management Console (MMC) are missing or corrupted. These files include the following:
To resolve this issue, follow these steps:
a) Click Start, click Run, type cmd, and then click OK.
b) At the command prompt, type cd %windir%\system32, and then press ENTER.
Note: The %Windir% folder is the folder where you installed Microsoft Windows.
c) Type the following commands. Press ENTER after each command.
d) Type exit, and then press ENTER to close the Command Prompt window.
e) Restart the computer.
Hope the information helps. Do reply if you need further assistance, we will be happy to help you.
1 person was helped by this reply
Did this solve your problem?
Sorry this didn't help.
Great! Thanks for marking this as the answer.
How satisfied are you with this reply?
Thanks for your feedback, it helps us improve the site.
How satisfied are you with this response?
Thanks for your feedback.