My organization has been dealing with a frustrating memory error linked to SearchProtocolHost.exe on our Windows 11 laptops since last Wednesday. Users log in and launch Outlook normally, but then suddenly encounter a memory error with the message: "The instruction at Ox00007FFFFS69B93G referenced memory at 0x0000000000000000. The memory could not be read." Initially, we blamed a recent Office update because uninstalling Office resolves the issue, but reinstalling it brings the error back. Interestingly, this issue sometimes occurs even if Outlook isn't opened. We've researched extensively, tried fixes like running 'sfc /scannow,' rebuilding the Windows search index, completely removing and reinstalling Office, and even temporarily disabling antivirus software. We've got over 35 machines experiencing this, with no clear pattern as to why some machines encounter the issue while others don't, despite them being identical. New machines set up from a clean image don't show the error yet, but they may just not have encountered it long enough. I'd love to hear if anyone else is facing this unusual issue!
3 Answers
Have you tried using Procmon to capture events before opening Outlook? It might help identify what’s causing the error when it pops up. Just start the capture, trigger the error, then stop capturing and analyze the logs for any clues.
If multiple machines started having this issue recently, consider rolling back any recent updates or Office versions. Sometimes a patch can cause unexpected problems, and backing out those updates might clear things up.
I’ve noticed a similar glitch with taskhost.exe on Windows 11. My experience aligns with yours; the issue seems more prevalent in the 24H2 and 25H2 updates. I thought I had a solution, but it returned on one laptop the next day. I suspect there's an underlying problem with those specific versions.
We primarily run on 24H2 and 25H2, too, and have seen instability. Patching aggressively is a must for us in the financial sector, but it’s tough to exclude updates unless there's solid evidence of a problem from Microsoft.
I get what you mean about it being tricky to remove patches, but if you've got a recent update causing chaos, it might be worth pulling the January 2026 update and seeing if it fixes anything.