this is not working
this is probably the most useless problem report we get - and we get it a lot. It tells us nothing about what is happening, or when it happens.
So tell us what it is doing that you didn't expect, or not doing that you did.
Tell us what you did to get it to happen.
Tell us any error messages.
Use the "Improve question" widget to edit your question and provide better information.
Otherwise, we have to guess what might possibly be going wrong with your app!
In this guess, I see one obvious problem ... which may or may not be the one you have met!
Start with the documentation: Image.FromFile
Managed GDI+ has built-in encoders and decoders that support the following file types:
The file remains locked until the Image is disposed.
If the file does not have a valid image format or if GDI+ does not support the pixel format of the file, this method throws an OutOfMemoryException exception.
What the bit in bold
means is that the first time you click the button it'll load the two images: the second time it won't and your app will throw an exception.
Instead of that, load your two images into
Image variables as part of your
form constructor and use those as your button images.
Or better, add the images as resources to your application and use them directly from there.