Stuck at black screen after restarting to install MICROSOFTMDG

[Eulogy]

I've restarted to install the firmware update on my 950 like 20-30 minutes ago and it's stuck at a black screen since then. Pressing the main button lights up the 3 keys but that's all. I was on .63.

Should I start panicking?

 

[TheChazas]

Should not take so long, try soft reset, if not check with Recovery Tool.

 

[Eulogy]

I did a soft reset after about one hour of waiting. The firmware update started running and all went on fine. Phew!