I just notice a discrepency in your information about the state of this device:
2) ...... it was updated via GarminExpress,used only once and since then it got stuck on Garmin logo.
3) ....... Continuos boot loop on Garmin logo, without any message related to maps.
Those descriptions are not the same, "stuck" and "boot loop". When a device boots partially then sticks or freezes in the boot procedure it's usually much easier to get into preboot than when the boot cycles constantly. i.e it's constantly terminating and re-starting over and over. Boot-looping devices are particularly difficult to flash because there is only a very short window of opportunity to initiate a flash before the boot-cycle starts again. Persistence is key in regard to many stubborn bricked devices however your experience that V5.90 cure fw flash finishes (I guess you mean Updater.exe reported that the flash was successful) yet still there is no MSM access is concerning.

Please say which state it's in, stuck on logo or boot-looping.