Diagnosis
IE means 'Inlet Error'—it's not getting enough water, or the pressure sensor thinks it's not. The cold water inlet valve screen is the prime suspect for getting clogged with sediment.
How to Fix It
Turn off both hot and cold water valves behind the washer. Unscrew the cold water hose from the back of the machine. You'll see a small plastic filter screen inside the washer's inlet port. Use needle-nose pliers to gently pull it out. Rinse it clean under a faucet, clear any gunk from the port, and pop the screen back in. Reconnect the hose, turn the water back on slowly, and check for leaks.
If That Didn't Work
The water pressure itself might be too low, or the inlet valve solenoid could be faulty. Check that your household faucets have good pressure and the hoses aren't kinked.
Heads Up
Do the hot water inlet screen while you're at it. Sediment buildup is a when, not an if, with most home water supplies.