xbox dashboard taking to long to start?

Check your Internet Connection!! Check your hard disc Connection if you have any!! Hard reset the console by Long pressing the Power Button!! Remove the power cord for few mins and then Plug in!! And also try to Logout and then Login with your account!!
Sometimes switching through account’s work if you have two or more accounts logged in!!

Weird fix but - Go into Settings, Blu-Ray, Persistent storage, and clear the storage. After that your UI should be faster and smoother. I have to do this every few days or else it gets clunky, not a forever fix but it helps.

Press and hold the Xbox button
on the front of the console for approximately 10 seconds to turn off the console. Then press the
Xbox button again to turn the console on.

If that fails try and get the

Xbox Startup Troubleshooter again, follow these steps:

1. Power off your console, and then unplug the power cord to ensure that the console is completely powered off.
   
2. Wait 30 seconds, then plug the power cord back in.
3. Press and hold the BIND button (located on the left side of the console) and the
   EJECT button (located on the front of the console), and then press the
   Xbox button on the console.
   Note The Xbox One S All-Digital Edition does not have an
   EJECT button. You can bring up the Xbox Startup Troubleshooter on this console by holding only the
   BIND button (steps 3 & 4) and then pressing the Xbox button
   .
   
4. Continue holding the BIND and EJECT buttons for 10-15 seconds.
   
5. Listen for two “power-up” tones a couple of seconds apart. You can release the
   BIND and EJECT buttons after the second power-up tone.
   
6. The console should power up and take you directly to the Xbox Startup Troubleshooter.
   

To reset your console from the Xbox Startup Troubleshooter, use the
D-pad and
A button on your controller to select
Reset this Xbox. When prompted, select Keep games and apps. This option will reset the OS and delete all potentially corrupted data without deleting your games or apps.

What do you mean by reset? Have you tried unplugging the console for 1 minute yet? That usually sorts issues like that.

Hi, sorry to hear that's happening. For this issue, I'm guessing the error code you're getting with this message is likely 0x8027025a; if you're
getting a different error code, please let us know what error code you're getting. If you are getting error code 0x8027025a and you've already tried a

power cycle of your console without any success, I'd next recommend a
soft factory reset, where you select "Reset and keep my games & apps" when prompted.