Originally Posted by dkul

ENG 1 REVERSER status msg would appear on the center screen (EICAS) to alert the crew that the sensor "sensed" that the reverser on #1 engine (furthest outboard left side) was not stowed and locked and therefore could open uncommanded at any time (which is not a good scenario). Was probably just a case of a faulty sensor because if it had indeed opened at that moment the pilots would have felt the plane pull to the left. In a case like this, it would be safe to reset the sensor and try another take-off. If they had felt any kind of pull I am certain they would have done a gate return without hesitation.
The message indicates the rejects were at 60 and 82, so fairly "slow" for an airplane (anything below 80 is considered "low speed regime").