Arduino AVR boards later than 1.6.21 onwards- can't update Nano bootloader

[rushilsoni]

Cannot update Nano bootloader if version on Arduino AVR boards is newer than 1.6.21.
Nano goes into bootloop on Watchdog reset if old bootloader is used

[per1234]

Which programmer are you using?

[rushilsoni]

Using Arduino UNO in "Arduino as ISP" mode to burn the bootloader to Nano. Works fine if Arduino AVR Boards is downgraded to 1.6.21

[per1234]

Closing as duplicate of #8032