Hopefully, the problem is just a simple internal fuse that has burnt out. When electricity shuts off suddenly and in some cases comes back on a few seconds later what happens is that it has a power surge somewhere and travels down the line, down the service drop that comes from the pole into your breaker box and hit devices plugged into the outlets. Sometimes the power surge is not strong enough to trip the breakers in your panel, but is strong enough to cause internal fuses to blow or cause serious damage to internal electrical components. Sometimes a lightening strike can happen and fry just about everything you have plugged into an outlet.
If the player will not come on at all, the first thing you may want to check is the outlet itself. Most homes now are required to have what is called GFCI (ground fault circuit interrupters), which basically acts as a circuit breaker. The outlets have red reset buttons on them and can be reset by pushing the reset button back in. I do not know if your home contains these, but that should be the first thing you want to check.
If you do not have GFCI outlets, you may want to take another electrical device and plug it in the outlet and see if the device operates properly. You are doing this just to make sure nothing has happened to the receptacle itself. If everything works normally, you know the problem is not in the outlet and can move on to the next thing to check. If the new device does not work in the outlet, then there may be an internal malfunction in the outlet and will need to be replaced.
Now that you have confirmed that the outlet is ok, you can now take a screw driver (usually phillips head tip) and remove the dvd players case so you can check for an internal fuse. When you open the case, the fuse should be located fairly close to where the plug itself goes into the device. The fuse will be held in place by a little bracket at each end and you can easily pop the fuse out, but be careful to not break the fuse or cause any other damage to the brackets or circuit board. Hold the fuse up if the container is clear and look at the filament inside and see if it has been burnt in half or if there is a burnt spot on the inside of the glass container itself. Sometimes the fuse my be coated and you will not be able to see inside, so it is better if you go ahead and replace it with a new one.
Here are couple of pictures to give you and idea of what you are looking for:
Closer view of the fuse
You can see the fuse located near the large black capacitor
After you have replaced the fuse, you can now plug the device back in and test to see if it is now functioning properly. Be really careful to not touch anything inside the device as this could cause you to be electrocuted. As soon as you know the device is working properly now, turn it off and unplug it from the outlet and replace the cover.
If the fuse looks ok to begin with, then there is a possibility that the cord is messed up (it is not really that common, but it can happen). The worse case scenario is that one of the other electrical components has malfunctioned and it is recommended that you have an experienced technician find and fix the component, because if you do not really know what your doing it can cause injury to yourself or cause other serious damage to the device. I have witnessed the fuse not being blown and a power surge still cause electrical damage to the other components, so it can happen.
I hope this gives you an idea of what the problem may be and some instruction on how to solve it. If you need further assistance, please feel free to post a comment with any other information you may require. Please include the brand name and the model number of the device as well.
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