How to add MOLDREF99 into MapInfo

Open Mapinfo projection file (C:\Program Files\MapInfo\Professional\MAPINFOW.PRJ) and add the following line at the begging of the file

"--- Moldavian projections ---"
"MOLDREF99\p4026", 2008, 33, 7, 28.4, 0, 0.99994, 200000, -5000000, 0, 0, 400000, 400000

Restart Mapinfo.