Saving issues

I don't know if I'm the only one having this issue, but since I started using the Beta I'm not able to save my project. For every manual save I have to choose a new name using 'Save as...', because there is an unnamed error that prevents saving the file in the same location.
Is it possible that this error occurs because I am saving on my dropbox (of course not directly, but in a dropbox-synchronized folder/drive)?