Range reference - how to change from RC back to the standard reference?

Hi this is a complete noob question.

My Excel was crashing today while doing a Vlookup. When i restarted I notice the range references were in the format of RC e.g. row 1, column 1 would be RC[-1].

How do I get it back to the standard row and column syntax?

Cheers
Talan

Tools > Options > General, untick R1C1 reference style