Sharepoint Site Error: Server error: http://go.microsoft.com/fwlink?LinkID=96177

When users attempt to access a SharePoint site, they encounter the following error message:
Server error: http://go.microsoft.com/fwlink?LinkID=96177

Event Viewer has the following error description:

The schema version (3.0.149.0) of the database DATA
DATABASE_NAME on DATABA_SESERVER_NAME is not consistent with the expected database schema version (3.X.X.X) on DATABASE_NAME. Connections to this database from this server have been blocked to avoid data loss. Upgrade the web front end or the content database to ensure that these versions match.

Event Type: Error
Event Source: Windows SharePoint Services 3
Event Category: Database
Event ID: 3760
Date: xxx
Time: xxx
User: N/A
Computer: xxx
Description:
SQL Database 'SharePoint_Config_eb15c91e-319d-4337-81f6-55e6f03693c4' on SQL Server instance 'np:\\.\pipe\MSSQL$Microsoft##SSEE\sql\query' not found. Additional error information from SQL Server is included below.

Cannot open database "SharePoint_Config_eb15c91e-319d-4337-81f6-55e6f03693c4" requested by the login. The login failed.
Login failed for user 'domain\svcacct_sharepoint'.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

Event Type: Failure Audit
Event Source: MSSQL$MICROSOFT##SSEE
Event Category: (4)
Event ID: 18456
Date: xxx
Time: xxx
User: domain\svcacct_sharepoint
Computer: xxx
Description:
The description for Event ID ( 18456 ) in Source ( MSSQL$MICROSOFT##SSEE ) cannot be found. The local computer may not have the necessary registry information or message DLL files to display messages from a remote computer. You may be able to use the /AUXSOURCE= flag to retrieve this description; see Help and Support for details. The following information is part of the event: domain\svcacct_sharepoint, [CLIENT: ].

Event Type: Error
Event Source: Windows SharePoint Services 3
Event Category: Database
Event ID: 3760
Date: xxx
Time: xxx
User: N/A
Computer: xxx
Description:
SQL Database 'SharePoint_Config_eb15c91e-319d-4337-81f6-55e6f03693c4' on SQL Server instance 'np:\\.\pipe\MSSQL$Microsoft##SSEE\sql\query' not found. Additional error information from SQL Server is included below.

Cannot open database "SharePoint_Config_eb15c91e-319d-4337-81f6-55e6f03693c4" requested by the login. The login failed.
Login failed for user 'domain\domain_admin_account'.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.


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Resolution:
Stop all IIS Sites

open command prompt
navigate to:
%COMMONPROGRAMFILES%\microsoft shared\web server extensions\12\bin

run the following command:
stsadm –o upgrade –inplace –url Central_Administration_URL –forceupgrade

(where Central_Administration_URL is the url for the sharepoint central admin site)

Once command ends successfully, restart all IIS sites