Bad Office Click-to-Run (and installed MSI version?) update blamed for Outlook freeze

Lots of reports this morning about Outlook freezing on start.

From an anonymous poster on AskWoody:

Today when I went to check my email, Outlook would not open; it would load the “Starting Outlook…” splash screen, which would close without opening the Outlook window itself, and the taskbar icon went away. Looking in Reliability History, it states that Outlook has crashed.

I tried opening in safe mode (it does the exact same process as described above) and restarting the computer to no avail. I even tried the full repair (not the quick one), redownloading and reactivating MS Office 2019, but no go.

Quintalis on Reddit:

Outlook immediately crashing on open after patching last night

Even in safe mode, appcrash. Full online repair no good, rolling back updates, anyone seeing this?

edit: appcrash, exception code 0xc0000005, re-install no good, rollback no good. We also regedited for sigred mitigation last night, I’m tempted to temporarily undo that and test…

edit2: temporarily unpatched sigred, tested, not the culprit!

edit3: Had some copies of Office 2019 C2R lying around, installed version 1808 (Build 10363.20015 Click-to-run) and it’s working. Yay?

From tenebrousrogue:

I’ve got a fix, after this hit several of our clients. Performing a rollback fixed it, must be a bad office update. open cmd, run:

cd “\Program Files\Common Files\microsoft shared\ClickToRun”

then:

officec2rclient.exe /update user updatetoversion=16.0.6366.2062

EDIT: u/peEtr had success as well, with a more recent version (June24th). Change the second command to:

officec2rclient.exe /update user updatetoversion=16.0.12827.20470

Additional reports (1, 2, 3)

UPDATE: From @rpodric

I assumed the update they were talking about was server side, since I’ve been on the same C2R (Beta) build for a week, but who knows. Nothing should have changed build-wise here. My third attempt running it this morning was successful somehow.

In the past few minutes, Microsoft has acknowledged the bug, but you’re on your own. “As a workaround, users can utilize Outlook on the web or their mobile clients.” Golly. My PC doesn’t work for email, so I need to whip out my iPad?

ANOTHER UPDATE: Microsoft says “We’re rolling out a fix for this issue, and we expect the mitigation to reach all customers over the next few hours.” No details about version numbers – or even the method being used to roll out the fix.

Says Ralph Carothers: “So, by reach them do you mean its going to back door patch them? Because this happened middle of the day to most of the users I’ve had impacted, and I certainly didn’t push out a patch.”