Here you go
winerr 53 means "The network path was not found". If you got this message, it means the client stack cannot find the target machine. Here are possible reasons for this failure,
a) typo in the server name, or using "/" rather than "\" between server name and instance name, e.g. "myserver/myinst" is not correct.
b) name resolution to the server name is not correct, "ping -a yourserver" would tell if that's the case
c) The server machine is firewall'ed and file sharing is not in the exception list. You need put "File and Printer Sharing" in exception. (from below link)
Named Pipes Provider, error: 40 - Could not open a connection to SQL Server (Microsoft SQL Server, Error: XXX)[
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SQL SERVER – FIX : ERROR : (provider: Named Pipes Provider, error: 40 – Could not open a connection to SQL Server) (Microsoft SQL Server, Error: )[
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