In the master bathroom we have a stand-up shower and an adjacent bathtub. When taking a shower the water begins to back up and overflow the shower, then it will slowly drain. Also, after using the bathtub and draining the water, the shower again backs up and overflows into the bathroom and leaves a gray deposit of some type. We have used a snake in the stand up shower and nothing happened. We also tried the snake in the drain opening pipe outside the house and nothing came out. Should I try running the snake down the vent above the bathroom? Any other suggestions on what I could do to solve this problem?

Thanks, Jason

Close the bathtub drain.
Remove the cover on the shower drain to expose the drain pipe.
Turn on the shower until water backs up into the bottom.
Using a wet/dry shop vac place the hose firmly on the drain to seal the gap and turn it on. It will usually suck the obstruction out due to the added water pressure. If this does not work you can also use the blower function if shop vac is equipped by repeating all the steps and using blow instead of vac.

The problem is that either you didn't put out enough snake to reach the blockage or the cable was too small to do any good. Try the shop vac but if that doesn't work go back to the snake.
You may snake from any one of three spots. 1) go down the shower drain. Put out 20 feet of snake.
2) remove the chrome overflow plate on the bathtub and go down the tub waste. Again, put out 20 feet.
3) go down the lavatory roof vent. Put out enough cable to reach the base and 20 feet more. Good luck, Tom