Kohi script

Kohi script is an undeciphered writing system used in Gandhara, in what is now Afghanistan and Pakistan, from the first to the eighth century AD.
Dr. M. Nasim Khan (TI), a Pakistani archaeologist, was the first to discover inscriptions written in a previously unknown script. The name Kohi for the script was also first coined by Dr. Nasim Khan. Since 1999 he has been working on its history and decipherment and thanks to his efforts the actual name of the script which is Puṣkarasāri, mentioned in different ancient literatures, has now been identified.
This writing system bears some resemblance to both Brahmi script and Kharosthi script.
==Reference==
Kohi script from Gandhara, Discovery of Another Ancient Indian Writing System, by M. Nasim Khan, Gandharan Studies, vol. 1, pages 89–101 - which can be found here.
The Wikipedia page is 
Category:Undeciphered writing systems
Category:Middle Ages