SQL DBA Blog: Home
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Could Not Open a Connection to SQL Server: Error 53 and Named Pipes Error 40
🚨Part of the SQL Server Errors series, the exact messages and what actually causes them.Related pillar: Server & Configuration Error 53 · Named Pipes Provider · error 40 A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name…
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SSPI Handshake Failed in SQL Server (Error 17806)
🚨Part of the SQL Server Errors series, the exact messages and what actually causes them.In: Security Windows authentication reached SQL Server and Windows refused the account before any login was checked. The error log gets 17806, the client usually gets 18452, and no SQL Server setting will fix it. Error 17806 · Severity 20 · …
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Violation of PRIMARY KEY Constraint and Cannot Insert Duplicate Key (Errors 2627 and 2601)
🚨Part of the SQL Server Errors series, the exact messages and what actually causes them.Related pillar: Performance & Troubleshooting Msg 2627 / 2601 · Level 14 · State 1 Msg 2627, Level 14, State 1 Violation of PRIMARY KEY constraint ‘PK_ErrDemoPk’. Cannot insert duplicate key in object ‘dbo.ErrDemoPk’. The duplicate key value is (1). ⚡Half…
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The Server Principal Is Not Able to Access the Database (Error 916)
🚨Part of the SQL Server Errors series, the exact messages and what actually causes them.Related pillar: Security Msg 916 · Level 14 · State 2 The server principal “ErrDemo916” is not able to access the database “DemoDatabase” under the current security context. ⚡Check the database, not the login: the named database has no user mapped…
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Login Failed: The Account Is Disabled (Error 18470)
🚨Part of the SQL Server Errors series, the exact messages and what actually causes them.In: Security Msg 18470 · Level 14 · State 1 Login failed for user ‘ErrDemoDisabled’. Reason: The account is disabled. ⚡Enable is one line; the real question is why it was off. sys.server_principals modify_date tells you when it changed, and the…
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Cannot Insert the Value NULL Into Column (Error 515)
SQL Server error 515 names a NULL you may never have written. Leaving a NOT NULL column out of the insert produces the same message, and a default fixes that case but not an explicit NULL.
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Login Failed: The Login Is From an Untrusted Domain (Error 18452)
🚨Part of the SQL Server Errors series, the exact messages and what actually causes them.Related pillar: Security Msg 18452 · Level 14 · State 1 Login failed. The login is from an untrusted domain and cannot be used with Integrated authentication. ⚡Check the account before you call the domain team. When I see this it…
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Could Not Allocate Space Because the Filegroup Is Full (Error 1105)
🚨Part of the SQL Server Errors series, the exact messages and what actually causes them.Related pillar: Storage & Capacity Msg 1105 · Level 17 · State 2 Could not allocate space for object ‘dbo.Orders’.’PK_Orders’ in database ‘YourDb’ because the ‘PRIMARY’ filegroup is full due to lack of storage space or database files reaching the maximum…
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A Read of the File Succeeded After Failing (Error 825, the Read-Retry Warning)
🚨Part of the SQL Server Errors series, the exact messages and what actually causes them.Related pillar: Backup & Recovery What Msg 825 Says Msg 825 · Level 10 · State 2sys.messages template Error: 825, Severity: 10, State: 2. A read of the file ‘%ls’ at offset %#016I64x succeeded after failing %d time(s) with error: %ls.…
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Lock Request Time Out Period Exceeded (Error 1222)
🚨Part of the SQL Server Errors series, the exact messages and what actually causes them.Related pillar: Blocking & Locking Msg 1222 · Level 16 · State 51 Lock request time out period exceeded. ⚡Find the blocker, not the victim: sys.dm_exec_requests shows who holds the lock, and the classic culprit is a session sleeping with an…
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- DBA Scripts: Get Failed Login Summary
- Query Was Fast Yesterday, Slow Today: Find What Changed
- The Current Transaction Cannot Be Committed (Error 3930)
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