Data Recovery and Disk Utilities Forum @R-TT

Tried to understand from the help but not found the answer. If I have image just c partition if it has bootable session or not.? What happened if I do restore just this C partition on another HDD (c partition), will such restoration (or wiil try) to update boot session????

Yes, you can, in general case.
You need to enable Primary (Active) on the Restore/Copy Parameters panel.
Still, there may be problems, if the configuration of the system is not standard. For example, the pagefile.sys file in the original configuration may be on other logical disk, and that may cause problems.

Thanks for you answer. Does it mean that RDI will update (or will try) bootable records regardless I do restoration just C partition only ?

Yes, if it is necessary.
Most likely, your old C partition is already set active, thus R-Drive Image will not change the boot sector.