DMJ

Just had another machine come in with the issue I described above. Fully removing Malwarebytes with the Support Tool and installing the beta fixed the issue in that case. So I'm pretty sure now we're at the end of that problem. Thanks everyone!

Ironically, the issue appears to have stopped since I posted about it. Haven't seen a computer with this issue since Monday. Funny how that works. Hopefully the trend continues! Just out of curiosity, did you also notice the whole computer coming to a crawl while the scans were running, or just the scans taking forever? With any luck, it appears that whatever the issue was may have been resolved. Fingers crossed.

Thank you, I've downloaded the latest beta from the thread you linked and will try it on the next machine I see with the issue. I don't have any more on the bench that are acting up at this moment, but just got a call from a customer this morning who appears to be having the issue, and will be bringing it down, I'll keep you updated.

Typically, Malwarebytes is the only security software on the machine. I have seen the issue with both manual threat scans and scheduled scans. I have not seen it on custom scans, mostly because we do not typically run custom scans.

I am a technician at a small computer repair shop. We have been installing Malwarebytes on our customer machines for a number of years and recommending them to purchase the full version of the software. Recently, beginning within a week or so ago, we've noticed severe performance issues with the latest version of Malwarebytes. Scans on some machines are taking 16 hours or more, or even multiple days sometimes. The issue does not seem to be with every machine, although I have not been able to discern much of a pattern as to which machines are affected and which are not. Some have had the free version while others the premium. Some have been decent quality hardware while some have been low-budget or old hardware. All have been running version 4.0.4 and all have been running Windows 10 build 1909. I don't know if other versions or builds of Windows are affected, as we don't have a particularly large number of machines come through here to really thoroughly experiment with. Computers that have this issue with Malwarebytes scans have system performance issues overall, causing the computers to run painfully slow, even on good hardware. Malwarebytes refuses to uninstall (The uninstaller freezes), and reinstalling or repairing with the Malwarebytes Support Tool does not fix the issue. Completely removing Malwarebytes with the Support Tool does fix the performance issues system-wide, but reinstalling Malwarebytes afterward then reintroduces the problem. Windows repairs such as DISM, SFC, and in-place upgrade installs also do not resolve the issue. SFC has found corruption on about half of the computers we've seen with this issue with Malwarebytes. This seems to affect perhaps 5-10% of the machines we have seen over the past week or so, but is clearly caused by Malwarebytes. We have been quite happy with Malwarebytes until now and would like to feel good about continuing to recommend it to our customers. However, these issues are making it difficult. We would like to get this resolved. Please advise.