I have changed to a question rather than issue as issue is for bugs not help/questions.
That connection string doesnt look correct to me.
It should look something like;
Data Sourse=PCName\SQLInstanceName; Database=SambaPOS,; User Id=sa; Password=1234;
Your missing the sql instance name from the datasource. Not sure id no DB name defers back to a default if not set but good practice to set so you know what the database is called.
Thanks for help, i found problem.
Problem is SQLBrowser Offline and i fix it
Yusuf bey Türkçe destek için https://destek.sambapos.com adresini kullanabilirsiniz.