How to fix Error 2333 on Windows Server 2025 / Windows 11

by

Troubleshooting Guide: Error 2333 — “Invalid source character 0x%02x”

Why This Error Happens

Error 2333 occurs when SQL Server’s character conversion engine encounters a byte sequence in the source data that does not map to a valid character in the specified codepage or collation. This is typically caused by mismatched encoding between the source file (e.g., a flat file used in BCP, BULK INSERT, or SSIS) and the collation/codepage configured on the destination table or server. It can also result from file corruption, an incorrect -C codepage flag during bulk operations, or binary/non-text data accidentally being parsed as character data.

Step-by-Step Resolution Guide

Step 1: Identify the Actual Source Encoding

  • Open the offending source file in a hex editor (e.g., HxD) or VS Code with encoding detection enabled to confirm whether it is UTF-8, UTF-16LE, ANSI, or a legacy DOS codepage.
  • Check for a Byte Order Mark (BOM) at the start of the file — SQL Server’s bulk tools can misinterpret files with or without an expected BOM.
  • Run file.exe (via WSL or Git Bash) against the file for a quick encoding guess: file -i sourcefile.csv.

Step 2: Correct the Codepage/Collation Mismatch

  • If using BCP, explicitly specify the correct codepage flag, e.g., -C 65001 for UTF-8 or -C RAW to bypass conversion entirely.
  • If using BULK INSERT, set the CODEPAGE option explicitly in T-SQL:
  BULK INSERT dbo.TargetTable
  FROM 'C:\Data\sourcefile.csv'
  WITH (CODEPAGE = '65001', DATAFILETYPE = 'char');
  • Verify the destination column collation matches the expected character set using sp_help 'dbo.TargetTable' or SELECT name, collation_name FROM sys.columns WHERE object_id = OBJECT_ID('dbo.TargetTable');.

Step 3: Re-save or Convert the Source File

  • Use PowerShell to re-encode the file into a SQL Server–friendly format:
  Get-Content 'C:\Data\sourcefile.csv' -Raw -Encoding UTF8 | Set-Content 'C:\Data\sourcefile_fixed.csv' -Encoding Default
  • If the file originated from a non-Windows system (Linux/macOS export), strip any stray non-ASCII control characters using a text editor’s “Clean” or “Normalize Encoding” function.
  • Re-run the import job after saving the corrected file.

Step 4: Repair or Rebuild the Import Format File (If Applicable)

  • If using a .fmt format file for BCP, confirm the field terminators and row terminators match the actual file structure rather than assumed defaults.
  • Regenerate the format file using: bcp dbo.TargetTable format nul -c -x -f C:\Data\TargetTable.xml -S ServerName -T.
  • Confirm Windows Server 2025 regional settings under Control Panel > Region > Administrative > Change system locale align with the expected source codepage.

Alternative or Verification Steps

  • Re-run the bulk import or SSIS package and confirm Error 2333 no longer appears in the SQL Server Error Log (EXEC sp_readerrorlog 0, 1, '2333';).
  • As an alternative, load the file into a staging table with an NVARCHAR(MAX) catch-all column first, then use TRY_CONVERT in T-SQL to isolate and clean the specific invalid characters before moving data to the final target table.