It is clear that you do not comprehend how to go about using a 0-5V MCU output to control a 12V load such as your solenoid driver. What are you doing - cutting and pasting circuits from the internet that you know not how they work?

Your solenoid driver circuit needs a lot of help. First off the transistor driver you show to drive the relay coil will never work from a 5V MCU output. Take a look at the FAQ here for ideas on circuits that can drive a relay coil. http://www.8052.com/faqs/120512

Secondly, the coil of your relay is only hooked up on one side. switching voltage to one side of the coil whilst leaving the other side open will not cause the relay to work. The first schematic in the above linked FAQ (which I posted here years ago) will give you a clue as how to connect up your relay coil.

Third, the load contacts from your relay to the solenoid will do nothing to energize the solenoid as drawn. You show that the relay contact will simply cause a grounded short across the solenoid coil. Instead you need a connection from a suitable power source to one side of the solenoid coil. Then the other side of the solenoid coil will connect to a relay contact (N.O. or N.C. as suits your needs). Finally the COM terminal of the relay would connect to the other side of the "suitable power source".

Note that the relay can be used to isolate the solenoid power control from the MCU control circuit. As such there is may be no need to connect any of the relay contacts to the MCU ground or power - unless you are using the same supply to control the solenoid.

BTW - I would change terminology in your description from 'canal' to hallway, room, vestibule or other such word. Normally a canal is a passageway used to control flow of water and I suspect that users of your security system would not get much joy having to swim through your security system - that is if you were successful at getting an under water design to work correctly and safely.

Michael Karas