I don't have electric locks but, my passenger door wouldn't open when I bought my car. I took off the door panel and the door mechcanism were so gummed up with dirt, grime and grease they just stopped moving. Older cars have these problems with build up of stuff. After I cleaned them and re-grease now it works like a champ. Hope this helps.
If you crank down the window, you can use a long screwdriver, placed vertically down inside the door to manually click the lock. I know that this is vague, but there is a tab that you can push down on that will pop the door open. Then, you can get the door panel off and pull the latch to determine what is going on. Sometimes, it can be as simple as needing to adjust the actuator lever from the outer door handle to the latch mechanism. A slight adjustment can sometimes keep the door from opening, especially if the door has been locked and then unlocked. Not sure why it happens, but it does.