"Ouch! 500 Error
Something went wrong.
We monitor this sort of thing, but if you are an authorized support contact, you should create a support ticket."
1. Clear Browser Cache
2. Try a different browser
3. Try a different device
4. Try a different internet connect (Hotspot/Tether from mobile)
If you still have any issue after trying all these steps, please contact Marketo Support for further assistance.