Can´t authorise or deauthorise my computer

I have the same problem with Digital Editions. I have read many forums and guides from Adobe where they say I have to find and delete a file on my MacBook which will allow me to deauthorise and authorise again but I cannot find that file even though I have followed all the steps and tried to find it multiple times. I can't earse the authorisation on my computer, cannot add new books to my library and cannot even authorise my e-reader, I've also tried uninstalling and installing Digital Editions a couple of times and changing my password but nothing is working.