This happens to lots and lots of people. Most of the time it is because of a depreciated function and a few tweaks here and there will get the extensions to work again. Now people do not like coding and they can switch off the error messages but that is not really a solution.
So here I am going to post all solutions that I needed to use for other websites and hopefully these are also helpful for you. From all the solutions posted I also contacted the developer either by forum or email to ask if they wanted to update their extension. So hopefully most of the below entries are redundant in no time.
Feel free to share your errors with me solved or not. If you solved it yourself please let me know the details so I can make a proper post for it on this website and can contact the developer if you haven't done that already.