Cannot connect to database

[jmcilhinney]

I know how to connect database

I've seen no evidence of that so far.

i have posted the dbconnection code

No you haven't. You've been asked to over and over but you haven't done so. The fact that you haven't and think you have is evidence that you DON'T know how to connect to a database.

i think these 4 connstring must be the problem, 4th of them must be connected,

And yet you haven't even bothered to post the actual connection strings. You have, again, been asked over and over to do so but you refuse to. The code that builds the connection strings is not the connection strings. It's an easy task to run the code, get the values and post them here but you refuse to do so. You ask for help and you refuse to provide the information that we have asked for repeatedly in order to do so. You've wasted far too much of everyone's time already. I won't be making any effort to help you any further here or in any future threads.