I upgrade our web server from window 2003 to window 2012. and for some reasons, when i try to connect ms sql server, it does not work.
with below message

provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified

However, if I use another web server it works fine.

All are in the same AD and network
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Dave BaldwinFixer of ProblemsCommented:
I've never seen the web server itself connect to a database.  Programs written in ASP or PHP do.  And if the SQL Server is not on the same machine, then you may need to install the SQL Native Client on the web server machine.  Look in the ODBC manager on that machine to see if the SQL Native Client is installed.
Prakash SamariyaIT ProfessionalCommented:
There might be incorrect version of ODBC driver installed or missing ODBC driver to connect to database!
Please the version of ODBC driver installed or not! Install proper version and try!
EugeneZ ZhitomirskySQL SERVER EXPERTCommented:
you may need to adjust your Connection string and check IIS settings.
Did you use ODBC connection? try on this new server to create\test ODBC connection to your sql server..
Also check:
-- if sql server is running and you can ping it from web server
- review connection string
- check if this new server firewall is  blocking

SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified

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Vitor MontalvãoMSSQL Senior EngineerCommented:
ITsolutionWizard, do you still need help with this question?
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Windows Server 2003

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