Receiving Message that Says "Error 507: Unable to connect. Is the device turned on?"

Hello, this is my first time posting here. I recently created an app for an Arduino submarine that controls the motors and am having problems with the Bluetooth. I am able to pair the HC-05 Bluetooth adapter on my Arduino to my Android and have it appear on my Bluetooth selection on my list picker. However, the problem is that I receive the Error 507 message when I click on the selection. It appeared when I used the purple block call BluetoothClient1.Connect address, and it is still appearing even when I changed it to call BluetoothClient1.ConnectWithUUID. I don't know if the issue is related to the code, the type of phone I'm using, or maybe a mix of both. Is there anything I can do? I would appreciate any help that I can get. Thank you!

Picture of the code

Dear @blub_blub_blue welcome to the Community.
if I have correctly understood, you have already tried without the UUID ? (since the HC05 is a classic BT transceiver)
If yes, have you set the permissions at Android level ? (i.e. BT and fine location ?)

Does BlueTooth radio travel through water?

Yes, I tried it without the UUID. The Android is connected to the Bluetooth so it's not like the HC05 doesn't have permission to be paired with the phone.

You are right @ABG,
RF (and BT is an RF :slight_smile: )cannot work underwater unless using extra long waves, i.e. ELF (while BT operates @2.4 Ghz), or at very very little depth.
I was supposing that the "submarine system" had an antenna out of the water like a buoy dragged by the submarine :thinking:.
Anyway, @blub_blub_blue, given that the BT receiver antenna is out of the water, the permissions I was referring to, shall be given to the app, just pairing at Android level the phone (or pad) and the HC05 is not enough.
To verify that the communication effectively works, I suggest you to have a look to the tutorials of @Juan_Antonio : on his site ( you'll find plenty of Arduino code and AI2 app's on this matter. I'm sure that having Tx and Rx on a desk and not underwater and following his tutorials, you'll succeed in your task.
All the best !

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Hello, I got the app to connect to the Arduino by using another bluetooth apparatus. However, I still appreciate the help. Thank you

Dear Ryan,
thanks for your feedback. But, for sake of knowledge, do you really got it working "underwater" ? :swimming_man: