One of our Nuvi 710 (MTK chipset ver.2.90) suddenly stucks in 2035 year. The time is correct but date is on beginning of 2035. So the screen switched to night or day mode by incorrect way. I think it is ephemeris virus

What do we perform for neglect of error:

- reset (holding of right bottom of screen or holding screen with on-block),
- downgrading SW,
- playing with satellites services menu (warm and predicative warm start)

But it is no result!

Any suggestion or practice!?