I managed to solve the problem. It turned out that I was missing a / at the beginning of the geog_data_path.I have the same problem when trying to execute geogrid.exe.
Parsed 50 entries in GEOGRID.TBL
Processing domain 1 of 1
ERROR: Could not open ../WRF/geog/topo_gmted2010_30s/index
The data and the index file both exist in this path and they are not blank. I don't know how to solve this problem.