error code 0xc0e90002

Zuelia Taylor 0 Reputation points
2026-10-06T10:36:35.1066667+00:00

I couldn't take my exam today because Respondus LockDown Browser stopped working on my Windows computer.

I already had LockDown Browser installed and have used it previously without this issue. Today, when I attempted to access my exam, LockDown Browser would not work. I contacted my school’s technical support and followed their troubleshooting instructions, including uninstalling, downloading, and reinstalling LockDown Browser, but the problem is still occurring.

I am receiving error code 0xc0e90002, and Windows also says it cannot recognize or verify the publisher of LockDown Browser.

I also tried contacting LockDown Browser/Respondus support, but I haven't been able to speak with anyone who can help resolve the issue.

At this point, I do not know whether the problem is with Windows, a Windows security setting, or LockDown Browser itself. I need help determining why Windows isn't recognizing the publisher and why LockDown Browser will not run on my computer.

I can provide the exact error code and screenshots of the messages I am receiving.

Microsoft Edge | Other | Windows 11
0 comments No comments

1 answer

Sort by: Most helpful
  1. Emma1-N 13,430 Reputation points Microsoft External Staff Moderator
    2026-10-06T23:57:56.1+00:00

    Welcome Zuelia Taylor,

    I understand how frustrating this must be, especially when it prevented you from taking your exam despite having used LockDown Browser successfully before.

    To help determine whether this is a Windows trust/signature issue or a LockDown Browser issue, could you please provide:

    • A screenshot of the exact error message showing error code 0xc0e90002.
    • The exact version of Windows 11 you are using. Press Windows + R, type winver, and share the version shown.
    • When you right-click the LockDown Browser installer or executable file and select Properties > Digital Signatures, do you see a Respondus signature listed?

    In the meantime, please try these quick checks:

    • Open Windows Security > Virus & threat protection > Protection history and see whether Windows Security has recently blocked or quarantined any LockDown Browser files.
    • Open Windows Security > App & browser control > Reputation-based protection settings and check whether there are any warnings related to the application.
    • Download a fresh copy of LockDown Browser directly from your school's learning portal or official Respondus-provided link rather than using a previously saved installer, then compare whether the new installer shows a valid publisher under Properties > Digital Signatures.

    Looking forward to your update.

    Was this answer helpful?

    0 comments No comments

Your answer

Answers can be marked as 'Accepted' by the question author and 'Recommended' by moderators, which helps users know the answer solved the author's problem.