How to fix no power due to plugging dvd rom while pc is on

[Jeckayu]

I found out that dvd was not working then upon checking my cpu,the supply cable wasn't plugged in so i plug it in. My pc instantly shuts down and won't open again. Mouse lights up but fan and push button switch is not working at all. Can i do something about it ?
A friend told me that it is a big no no to plug and unplug whatever inside the pc while it is on but she doesn't know what to do either. Please help me. Thanks

 

[PC-4LIFE]

Always make sure your system is off before making any hardware changes. Unplug the dvd drive and test again. Recheck any and all cables in your system, unseat and reseat them. If there is still no change, do the paperclip test on your power supply unit. It's unlikely there's a problem with the PSU, since your mouse turned on, but check anyway.

 

[hang-the-9]

Reset the BIOS (unplug system, pull the CMOS battery for about 10 seconds. With the system unplugged hold in the power button for about 10 seconds, plug system back in an see if it boots). If that does not work, power supply may be dead.

 

[ChaoticWolf]

That is one of the worst things you could possibly do to a system while it is on. Don't do that.
Always fully turn off the system and unplug it before making any changes inside it
Try unplugging the system, holding down the power button for a few seconds, plug it in again and see if it boots up
Try to clear the CMOS, by taking out the battery (some motherboards, the battery will not come out, if it doesn't look for the bios jumper)
Nothing else works then I guess your PSU is toast.