Android Question blutooth pairing problem

Hello evryone,

i am now working on app in B4A ,that in my app there is a blutooth connection section,i now researching about blutooth connetion,recently i read a post in this link that there were a project in this subject but when i press scan button in app, start searching nearby bluetooth,it found devices correctly ,when i click on any founded devices,start connecting to that,but no reciving pairing request or any password requiring section and connecting fail and apear Erorr connecting.

Apeared Erorr is:
Erorr faild,socket might closed or timeout,read ret:-1

Note:I want a code that like this app search and connet to any blutooth devices that user select it after found.

whats your view about this problem?
how can i solve it?
where of code is not correct?

sincerely yours.


Last edited:


Staff member
Licensed User
as discussion in post even i add start service BTPair and manifest change,as erel said.but any pairing request or passsword requre not apear and app show erorr like attached picturs erorr .
This discussion is not relevant.

Erorr faild,socket might closed or timeout,read ret:-1
You can only connect to a device that is listening for connections. Run the chat example on the two devices.
so thanks Erel, but i want to connect to selected found bluetooth device ,that include pairing request like usual connecting to other bluetooth.

so, how can i change the code?


Well-Known Member
Licensed User
what is reason of this Erorr?
how i can solve this Erorr?
I work with lot of obd2 Bluetooth device. You can get that error message with a defective bluetooth device, device not powered up while connecting or maybe using wrong com port (if applicable).
No,i can Connect to any bluetooth device from usual way in bluetooth settings and i see pairing request or pin and i can pair and unpair, but if i use this B4A app, it can find nearby devices but when i select device,connection faild Error apear.and do not receive any pairing request.
The error in the first post is related to the other device not listening for SPP connections.
When we connect from Bluetooth settings, pairing request can this also a type of spp connection?

if answer is yes, why in way if B4A app it doesn't work?

if answer is no, so how i make a app that work like bluetooth setings connection?