Everytime I try to check for software updates, it gets stuck on checking. I am on an old software program so I know that I need to update but I need to know how to do it from my PC. I don't understand why my phone isn't telling me that I need updates
There is no way to update the software from your PC to your HTC EVO. You will need to perform the update from Menu > Settings > System Updates > HTC software update > check now. 4.67.651.3 is the current version. You can verify what version your on by going to Menu > Settings > About phone > Software information.
I would highly recommend that you are connected to either Wifi or 4g service when checking and installing the update. This should take care of the getting stuck part that you are experiencing.
I do not have 4G in my area but I have tried it though Wi-fi. It just sits there and says checking but never finds anything. I have let it sit there, walk away from it, do other things and come back to the same thing.
power cycle your phone.(pull the battery for at least 2 minutes, hold down the power button for a few seconds, put battery back in and power up) and then try to search for the updates.