No, RealPlayer supports only .ram, .rmm, .ra, .rax, .rv, .rvx, .rm, .rmx, .rmvb, .rmd, .rmj, .rms, .rp, .rt, .mp3, .mp2, .m4a, .mp4, .mpg, .mpeg, .smil, .smi, .mov, .qt and .avi files. In order to open your .vo file, I suggest you try VLC Media Player. Also, download and install Combined Community Codec Pack.