“Critical Error – Start menu and Cortana aren’t working. We’ll try to fix it the next time you sign in.”

When I encountered this problem, none of the fixes in this article were any use. I use my PC on a network domain as well as stand alone. I encountered the issue first when logged into the domain. My non-domain profile still worked fine. Then a few days later, that one broke as well.

Having tried without success to rescue the profiles, I eventually deleted the domain profile, then recreated it.

This is when I discovered that when I changed my Edge settings in the "Open with" section to "A specific page or pages", this immediately caused the issue to return. When I logged off and back in, I chaged the setting back to "Start page" and the problem was resolved!

The Edge settings were identical in each profile - same web pages.

Could this be true? Does anyone else observe this?

Hi Ravinath,

I have had this error since June with the Insider builds. Each new insider build I installed would clear the error, but it would eventually come back(even after clean installs). Luckily I was able to create local admin accounts as a backup before the issue came up with the official release version. I haven't gotten rid of the 2 MS accounts that are experiencing this error since I have been hoping for a fix. I saw that this solution has been working for people for a long time now, but I am not able to log into the troubled accounts in Safe Mode with networking because it tells me that "The parameter is incorrect". I can log in with the non troubled accounts fine in safe mode. Any advice? 

Firstly what power icon? the only one is on the tower its self. So I couldnt try that fix.

I didnt know there was a function if right clicking on the security icon

I right clicked my security icon and there was no uninstal option so I couldnt try that fix. I then knoticed the compatability thing, ran that and now the windows is working again. This is too much hastle for something that claims to be simple. Bring back xp.

There is a pinned thread about this.

http://answers.microsoft.com/en-us/windows/forum/windows_10-start/critical-error-start-menu-and-cortana-arent/5256ebee-2c77-4003-87be-1597ab10cb4d

Here's what happened to me since I first commented...

I searched the Microsoft site furiously and fruitlessly for a phone number. I eventually found where you can schedule a MS tech to call you, which I did. The first tech (all from India, BTW) started a LogMeIn session and logged in as a hidden administrator. With this user all functionality was working fine. She had to escalate the call to a senior tech, and while she was on the phone with him trying to get him to take over the call, they were arguing about protocol, etc. I don't think the senior tech realized I was on the line and heard the entire exchange. The young lady had to get her supervisor to convince the tech to take over the call.

Once he took over the call he also took control of my PC using LogMeIn. He essentially created a new Administrator ("Test") and tested the functionality, which restored all functions, but without my user data. He instructed me to restart the PC, at which point the PC would not start. He had me turn off the PC for 15 minutes, in which time he left the call. He called me back in 15 minutes just after I restarted the PC and it (thankfully) came on. Then he proceeded to copy all of my user files from my user profile to the new user (Test). This took hours (overnight, in fact).

While on the phone I asked each of them how prevalent this issue was and they both admitted that it was a well known issue. The first tech told me that MS was working on a forthcoming solution, but did not know when it would be released. I think that was pretty much the standard reply. The second tech at first thought that I may not have a fully licensed version, so he ran some tests on my PC and determined that it is indeed fully licensed. The he told me that my PC may not be fully compatible with Windows 10. Background: My PC is a Dell XPS, about 3 years old) with plenty of memory and was delivered with Windows 7. I subsequently upgraded to Windows 8, then 8.1. Then, like everyone else, received the notification from MS about Win10 and that my PC was verified and eligible for the upgrade, which I installed in August, and worked fine for over a month - just past the 30 days in which you can revert to the previous OS. I was on the phone with them for nearly 4 hours.

In the mean time, after I logged in with the new user the next morning, I followed his instructions to convert the Test account (a local user) to an on-line account, which didn't go as smoothly as I anticipated, but I got through it. Now I have a new, on-line user which I renamed (but in the system it is still named "Test"). Everything seemed to be working, except...

When I started Outlook it behaved as a brand new installation having non of my mail, contacts, calendar, signatures, etc. I import the .PST file form the other user and that restored the data but not user preferences (signatures, category labels, etc.). I also had to reconfigure the iCloud control panel to sync with iCloud.

The other problem is that I now have two users with duplicate data on my C drive and as a result the drive is nearly full. I am in the process of moving data (photos, videos, music) off the C Drive to another internal drive I installed in an effort to regain space on the C drive and improve performance. The technician (second one who took over the case) was pretty good about calling to see how things went (per my request) and will call again on Monday to tidy things up.

Tried the Restart solution.  Did not work.  My Start Menu and search function is not working in Windows 10.   My other profile works for a while and then doesn't. 

Seems like one of the major reasons I upgraded to Windows 10 no longer works.  Epic failure on the part of MS it seems.