How to fix Error 3975 on Windows Server 2025 / Windows 11

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Troubleshooting Guide: Error 3975 – varchar(max) Not Supported for sp_getbindtoken

Why This Error Happens

This error occurs because sp_getbindtoken is used to create a bind token for distributed transactions across multiple connections, and this system procedure does not support large object (LOB) data types such as varchar(max), nvarchar(max), or varbinary(max). When a transaction context includes a session or query referencing these MAX data types while attempting to bind to another connection, SQL Server 2025 rejects the operation and aborts the batch. This is typically encountered in applications performing distributed or linked server transactions where large object variables are improperly passed between connections.

Step-by-Step Resolution Guide

Step 1: Identify the Query or Procedure Triggering the Bind

  • Review the application code or stored procedure that calls sp_getbindtoken or sp_bindsession.
  • Check SQL Server Profiler or Extended Events to capture the exact statement executing at the time of Error 3975.
  • Look specifically for variables or columns declared as varchar(max), nvarchar(max), or varbinary(max) within the transaction scope.

Step 2: Modify Data Types to Avoid MAX Types in Bound Transactions

  • Change varchar(max) columns/variables to a fixed-length equivalent (e.g., varchar(8000)) if the data size permits.
  • If large data truly exceeds 8000 characters, restructure the logic to process LOB data outside the bound transaction scope.
  • Update any affected table schemas using SQL Server Management Studio (SSMS) or via T-SQL:
  ALTER TABLE dbo.YourTable 
  ALTER COLUMN YourColumn VARCHAR(8000);

Step 3: Refactor Distributed Transaction Logic

  • Avoid passing MAX data types directly through sp_getbindtoken/sp_bindsession workflows.
  • Use a staging table or temporary table to hold LOB data separately, then join or merge results after the bound transaction completes.
  • Ensure MSDTC (Microsoft Distributed Transaction Coordinator) settings are correctly configured in Component Services (dcomcnfg.exe) under Windows Server 2025 if the issue is tied to distributed transactions.

Step 4: Apply Latest SQL Server 2025 Cumulative Update

  • Open SQL Server Configuration Manager and verify the current build version.
  • Navigate to Microsoft’s official download center and install the latest Cumulative Update (CU) for SQL Server 2025.
  • Restart the SQL Server service via services.msc or run:
  Restart-Service -Name 'MSSQLSERVER'

Alternative or Verification Steps

  • Re-run the original transaction/query after applying the data type change — confirm Error 3975 no longer appears in the SQL Server error log (Error Logs folder under C:\Program Files\Microsoft SQL Server\MSSQL17.MSSQLSERVER\MSSQL\Log\).
  • If the error persists, isolate the transaction without sp_getbindtoken entirely and use BEGIN DISTRIBUTED TRANSACTION directly, bypassing manual session binding as an alternative workaround.