How to fix flashing lint light on BOSCH WTMC6500?

The lint filter light flashes and dryer will not start.

I have removed filter, cleaned with warm water and soft toothbrush. Cleaned residual lint from bottom and sides of filter housing. Unplugged dryer overnite.
Checked again and light still flashes and unable to start dryer.

I removed the round plate on left side to peek at a possible problem, but uncertain what to do next.

I will try pulling out machine and checking exhaust hose and check where the hose vents out from side of garage as well....

Help!!!!

Of course, this almost 10 yr old dryer went out of warranty 10 days ago!!! This is the First time I didn't renew it!!!