How to resolve error "-.-" and not able to take pictures on an Olympus OM-D E-M10?

Start with the usual suspects:

• Turn off the camera and remove the battery. Let the camera sit overnight. Replace with a fully charged battery, turn the camera on, and see if the problem still manifests itself.
• Remove the lens. Try a different lens. Try the same lens on a different body. Clean the lens contacts on the lens and on the camera body.
• Reset all camera settings to the "factory default" settings. Some cameras require resetting at more than one place in the menu to reset everything.
• If nothing above works, refer it to Olympus authorized service.

Is the -.- at the bottom supposed to be a lens aperture? In which case this would mean that there is no lens or the lens is not detected (bad contacts in the mount, or defective lens or lens not supported, or added with a mount converter). This could also be the reason for MF. There could be some setting to allow taking pictures despite this (legacy/full-manual lenses).