Extremely Slow Performance Since Defender Was Pushed on Us

[VNJoe]

Compliance, Security, Protection, and Defender are all extremely slow, with responses from screen to screen ranging from 30 seconds to multiple minutes between clicking items and waiting for Microsoft cloud to return results.  I have a GB link and speed test well over 600 Mbps so it's not on my end.

It appears the cutover in late January to this new "Defender" platform has been extremely detrimental to the Office portal response times in these portals.

What is being done to resolve this?

[#2]

In case this is issue with the Defender connection to the cloud and you couldn't detect any issue issue from your side, I advise you to contact the Microsoft Support.

[#3]

They are well aware of it, I'm now getting community input so it actually gets addressed, or input saying it's just something on my tenant. Any input from the community confirming or rejecting this would be helpful.

[#4]

@VNJoe  Exactly the same here.....last 2 weeks its become almost unusable. I dread having to go in there ( which mid E5 rollout is not a great place to be)

[#5]

Since the Microsoft support is aware of the issue, then they will investigate and fix it. I advise everyone who is facing the same issue, contact the Microsoft Support and this way, you will help them to identify and fix the issue faster.

[#6]

@Reza_AmeriI don't think it has universally gotten any better.  I submitted feedback through the quarantine processing web page on a number of issues, including poor response time 5 to 30+ seconds. But there are other issues, including

1. the cumbersome page layout, where the information is at the top, with a large white area, and a button at the bottom. 

2. There is plenty of room to have one pane with block, report, and delete instructions on one page, but they are separate.

3. If you have the message list view, and select an option, it still opens the individual pane on the side for the message.

4. In a high resolution laptop screen, for example, a Dell XPS 9360, sometimes the buttons on the bottom aren't visible, and there isn't a vertical scroll bar.

5. In trying to block a message, I have had several instances where an error message pops up, pointing at a message that isn't in the quarantine, and which I recognize as a legit message. Is it incorrectly trying to delete messages it shouldn't? I can't tell. 

[#7]

In such case, Microsoft engineers need to investigate and the best is to submit feedback and people with same concern could upvote it.

[#8]

You said this exact thing a year ago. Scroll up.

[#9]

Your issue couldn't be fix by other troubleshooting steps like writing script , running commands and so on. Only Microsoft Engineers could review and release a fix. However, in case you want to investigate the issue yourself, then have a look at:
https://learn.microsoft.com/en-us/microsoft-365/security/defender-endpoint/troubleshoot-performance-...
You might find some clue there.

[#10]

@Reza_Ameri It could be fixed by allowing me to turn it off... Can you believe it filtered the notice there was a response to this post into quarantine? It'd be hysterical if it weren't true...

 Sad

[#11]

Turn off is not a solution, it is just to test if it works or not.
If you have another Anti-Malware solution, it will replace Microsoft Defender and turn it off.
Otherwise, turn it off will put your PC at risk.

[#12]

It gets better... I submitted it to them and they reclassified it as Bulk Mail... :D  It just needs to get out of the way of mail delivery, period.  Getting tons of complaints from customers about  valid emails being "lost" since they turned this on but decided NOT to notify end users by default.