How to gain S-OFF on HTC Salsa I want to root my HTC Salsa phone. According to this link I need to gain S-OFF on my Mobile.

There is nice article to gain S-OFF.

But my Question: Is there an alternative way, without using any hardware to gain S-OFF ?
the Salsa is supported by the official HTCdev bootloader unlock process

While this does not make your phone S-OFF (which would allow overwriting things like the radio software), it does make enough of the partitions writable to install custom recoveries like ClockWorkMod, root the device (by installing rooting packages like superuser or SuperSU), and install custom ROMs that don't need updated bootloaders (the vast majority).