@ghost43, I'm pretty sure I don't have a watch-only wallet and I didn't have any problems in previous versions. I solved the problem by going back to version 4.3.4 and then I was able to make a transaction without any problems. I don't know what the developers wanted to achieve with the new versions, but I personally don't like it and if they continue like this, Electrum will no longer be my first choice when it comes to hot wallets and smartphones.