Welcome to the world of supporting an outsourced office. I have such linguistic challenges on a daily basis. Ramesh almost certainly does know it's an OS. It will be dual boot, I'll put money on it.
If you think back we've had a lot of RH5 queries of late. I strongly suspect that support for a RH5 application has just been off-shored... Probably in the same place that was trying to get the Epson printers working in the other threads of a similar style.