Sofnology Exstemsia

Exstemsia v1.0 (1983-1992)
Exstemsia v1.0 was the first in the line of Exstemsia Operating Systems. Support for Exstemsia v1.0 ended on January 1st, 1992.

Exstemsia2 (1986-1996)
Exstemsia2 was released in 1986 and support for Exstemsia2 ended on April 7th, 1996.