Generating user instances in SQL Server is disabled. Use sp_configure 'user instances enabled'

I use the WVS 2005 for a while, and now would like to mirgrate the MDF to SQL Server. after adding the SQL server connection in WVS in show this msg...

'SQL Server is disabled. Use sp_configure 'user instances enabled' .........'

How come....

SOLUTION:

Type this shitty code in the SQL EXE windows...

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exec sp_configure 'user instances enabled', 1

Reconfigure

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Msg will show

'Configuration option 'user instances enabled' changed from 0 to 1. Run the RECONFIGURE statement to install.'