I didn't think a led driver is the same as a transformer.
You need a 12v 2amp transformer
Officially a driver is current controlled, however it seems anything DC today is called a driver, and the correct replacement has been got, both 12 volt both DC and both 2 amp so it should have worked OK. But polarity does matter so that seems most likely error.
Transformer is some this as the name suggests a device which transforms, so the one thing which maybe should not be called a transformer is the isolation transformer, as what goes in comes out and nothing is transformed, but we tend to think of a wire wound device where the ratio of input and output coils means it transforms the voltage as a transformer, and those devices are AC only and the frequency will not change, a switch mode power supply as used to allow front loading video recorders turns the AC to DC stores it in a capacitor then turns it into high frequency AC meaning the wire wound transformer can be a lot smaller, then it samples the output and changes the mark/space ratio of the unit making the high frequency AC to control the output to what is wanted.
The problem with this method is often there is a minimum as well as maximum output, this has caused problems with electronic transformers used for down lights etc. But in the main the units delivering DC volts are designed to work with no current output, the lighting ones with problems were in the main marked 20 - 105 VA or some thing similar so one is aware of the limitations.
Yes power supply is a better name to driver, transformer etc, but manufacturers call DC power supplies with fixed voltage drivers, so not much we as users can do, same as with MR16 compatible bulbs being called low voltage, we all know 12 volt is extra low voltage except for the Americans so it should say extra low voltage, but we are not as thick as the Americans and we can actually read the voltage.
