Clairejay, sorry you are having difficulties. Sounds like something got corrupted in yur system. Sometimes it's not so simple to uninstall and reinstall and you have to delete some extra folders during the process. The instructions are different depending on what kind of computer you are using. If you can state what OS you are using, then people might be able to offer more help. For example, are using a Mac or PC? What version of OS X or Windows are you using?
Here are two thread links that might point you in the right direction. One is for Mac and one is for Windows.
https://www.mobileread.com/forums/sho...45#post1296045
https://www.mobileread.com/forums/sho...d.php?t=113727