It looks like the parts repository on your system is corrupted in some what and it won’t sync with github. I’d reinstall Fritzing from the distribution zip file (which will replace the parts repository with an older version) and then wait for the update to complete. Fritzing will appear to hang for a long time (without any indication it is doing anything!) on the first execution but interrupting it before the update completes is usually fatal and requires the user directories to be moved aside or deleted.