End Google Ads 201810 - BS.net 01 --> Hi!

I am new to programming with SQL so I really need help on this one. After I finish an application with no errors or bugs, i tried to launch it in different computers. However, most computers encouter SQL errors while loading the application, either a timeout error or the application simply crashes due to the inability to load the data from an SQL database.

My questions are the following:

1. Do you need an SQL server running in the computer where you will deploy the application? Though in some computers, the application worked even though they do not have an SQL Server.

2. Should I modify something in the connection string when I am already deploying the software? Is there a difference in the connection string when the program is running in my computer and in other computers?

My connection string is this:
"Data Source=.\\SQLEXPRESS;AttachDbFilename=|DataDirectory|\\MyDatabase.mdf;Integrated Security=True;User Instance=True";

I tried modifying the timeout but the error still remains.


3. Where could I have missed something?

Sorry if I am missing something trivial here.

Thanks in advance for those who will respond! You'll really be helping me a lot.

Thanx!