Windows 10: "Protection definition update failed. Error code: : -2145095360" Win.10, Firefox, Dell laptop

My Microsoft Defender Antivirus will not update, and shows me this exact messagerotection definition update failed.Error code: : -2145095360Protection definition update failed. :This does not look like anything I have seen on this website in my searches, and I am worried. I tried re-booting and it didn't help either.Please help--and please write in language I can understand, as I am not a computer maven.I use Firefox, and no, I am not going to use Explorer or Google or anything else...have been using Firefox successfully for many years. This should not be happening.Thank you!

:)

 

Protection Definition update failed; Error Code -2147023278

I tried all of this and it still did not fix my error.

There were problems installing some updates, but we'll try again later. If you keep seeing this and want to search the web or contact support for information, this may help:

Definition Update for Windows Defender Antivirus - KB2267602 (Definition 1.259.209.0) - Error 0x80070643

protection definition update failed.

Error code: -2147023293

error description: fatal error during installation.

 

"Protection definition update failed. Error Code: -2147023278

I Haven't updated my windows defender since December last year I tried updating it today and got this:

"Protection definition update failed.

Error Code: -2147023278

Error description: Another installation is already in progress. Complete that installation before proceeding with this install"

Now the problem is I'm not installing anything so why is it showing this message?

* Original title: error message

* Moved from Windows 10/Security

 

Protection Definition update failed; Error Code -2147023278

Hi Robert,

Kindly refer to this support article for a detailed instructions on how to resolved error code 2147023278.

• How to troubleshoot definition update issues for Windows Defender

Let us know how it turned out.