Why can't I open 'settings'?

[AJITH_KR]

I have installed W10 IP 10149 build. After that, I made a hard reset. Unfortunately, can't open ''settings'' from action center. There is no settings in app list. Store beta also crashes while I try to open it.

 

[Willyman]

Same issue, exact same set of actions taken. Actually, internet explorer is also missing...

 

[Sabin V Abraham]

I have installed W10 IP 10149 build. After that, I made a hard reset. Unfortunately, can't open ''settings'' from action center. There is no settings in app list. Store beta also crashes while I try to open it.

I assume the migrations process didn't went fine. Use recovery tool to migrate back to previous version and then do a fresh install.
As informed inn the instructions, do not lock the screen or turn off for around 10 mins after upgrade. Because the migration will be still running in the background and locking / restarting may end up in a fuzzy state.