Comments by Member 9987570 (Top 1 by date)

Yes, very sure.
In SQLServer 2005 it is "CHACH-KOMPUTER\SQLEXPRESS"
but in VisualStudio2012 in the line with connection string I have to put two backslashes:
"CHACH-KOMPUTER\\SQLEXPRESS"
otherway it underlines the only one backslash in the code with little snake-line
"CHACH-KOMPUTER\SQLEXPRESS", something like that ;)
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