Forum Discussion
Outlook 365 suddenly won't open
Steven F, original poster here: my Outlook just fixed @ 1:20 Pm pst, I tried it and it opened right up. Hope the same for all of you, maybe 1 at a time! Thanks all.......
This fix worked - thank you so much for whoever shared this.
open cmd, run:
cd \Program Files\Common Files\microsoft shared\ClickToRun
then enter:
officec2rclient.exe /update user updatetoversion=16.0.6366.2062
Good luck
This worked for me as well! Thank you!
open cmd, run:
cd \Program Files\Common Files\microsoft shared\ClickToRun
then enter:
officec2rclient.exe /update user updatetoversion=16.0.6366.2062
This worked for me yesterday. Although it did take my Office back many versions. At least I can check my mail.
open cmd, run:
cd \Program Files\Common Files\microsoft shared\ClickToRun
then enter:
officec2rclient.exe /update user updatetoversion=16.0.6366.2062
Alex_LCTried that and it says I have the latest version, so I have to go into the task manager and shut outlook down then restart the program for it to run what bs.
This is an interesting read...
https://www.computerworld.com/article/3567096/outlook-went-down-for-four-hours-wednesday-what-happened.htmlEspecially the anonymous post that was posted on AskWoody, stating the below.
So it was no client side issue, there was no faulty patch, and no new patch to install.Question is then, what is Microsoft trying to change in regards with client authentication that they are unable to share ANY details about as part of what happened yesterday. To me it feels as if Microsoft is aware of some 0-day critical vulnerability they tried to patch yesterday - unsuccesfully as they had to undo the change - but can't share any details yet as explaining what happened would publicly expose the vulnerability. Just my gut feeling though... could just be a new feature too, but the timing and the way Microsoft is (not) communicating currently about what happened seems odd to say the least.
Can’t tell you my source but basically rumor is something was pushed server-side on Microsoft’s end in regards to a security or authentication change (who knows what specifically) and in that change it cut off communication with Outlook clients past a certain patch. I confirmed this was not last night’s patch that contained these changes, but one previously issued. I do not know anything more specific about this patch in question. This is why rolling back worked – it went to a client version that was before that change in how it talked to their servers. Why this was done in the middle of the day, I don’t know. Very unusual. All I’m willing to go into right now.
