diff --git a/Installer.Tests/Helpers/TestDatabaseHelper.cs b/Installer.Tests/Helpers/TestDatabaseHelper.cs
index 8f5b9f6..12ef5a4 100644
--- a/Installer.Tests/Helpers/TestDatabaseHelper.cs
+++ b/Installer.Tests/Helpers/TestDatabaseHelper.cs
@@ -66,7 +66,7 @@ CREATE TABLE config.installation_history
                     installation_date datetime2(7) NOT NULL DEFAULT SYSDATETIME(),
                     installer_version nvarchar(50) NOT NULL,
                     installer_info_version nvarchar(100) NULL,
-                    sql_server_version nvarchar(255) NOT NULL DEFAULT N'Unknown',
+                    sql_server_version nvarchar(512) NOT NULL DEFAULT N'Unknown',
                     sql_server_edition nvarchar(255) NOT NULL DEFAULT N'Unknown',
                     installation_type nvarchar(20) NOT NULL DEFAULT N'UPGRADE',
                     previous_version nvarchar(50) NULL,
@@ -108,7 +108,7 @@ CREATE TABLE config.installation_history
                     installation_date datetime2(7) NOT NULL DEFAULT SYSDATETIME(),
                     installer_version nvarchar(50) NOT NULL,
                     installer_info_version nvarchar(100) NULL,
-                    sql_server_version nvarchar(255) NOT NULL DEFAULT N'Unknown',
+                    sql_server_version nvarchar(512) NOT NULL DEFAULT N'Unknown',
                     sql_server_edition nvarchar(255) NOT NULL DEFAULT N'Unknown',
                     installation_type nvarchar(20) NOT NULL DEFAULT N'UPGRADE',
                     previous_version nvarchar(50) NULL,
diff --git a/install/01_install_database.sql b/install/01_install_database.sql
index 2d71820..8a9bddb 100644
--- a/install/01_install_database.sql
+++ b/install/01_install_database.sql
@@ -620,7 +620,7 @@ BEGIN
         installation_date datetime2(7) NOT NULL DEFAULT SYSDATETIME(),
         installer_version nvarchar(50) NOT NULL,
         installer_info_version nvarchar(100) NULL,
-        sql_server_version nvarchar(255) NOT NULL,
+        sql_server_version nvarchar(512) NOT NULL,
         sql_server_edition nvarchar(255) NOT NULL,
         installation_type nvarchar(20) NOT NULL, /*INSTALL, UPGRADE, REINSTALL*/
         previous_version nvarchar(50) NULL,
@@ -641,6 +641,34 @@ BEGIN
 END;
 GO
 
+/*
+Widen sql_server_version when upgrading from older installs (nvarchar(255) or narrower).
+Idempotent: no-op if the column is already nvarchar(512) or wider, missing, or table absent.
+*/
+IF OBJECT_ID(N'config.installation_history', N'U') IS NOT NULL
+BEGIN
+    IF EXISTS
+    (
+        SELECT
+            1
+        FROM INFORMATION_SCHEMA.COLUMNS
+        WHERE TABLE_SCHEMA = N'config'
+        AND   TABLE_NAME = N'installation_history'
+        AND   COLUMN_NAME = N'sql_server_version'
+        AND   DATA_TYPE = N'nvarchar'
+        AND   CHARACTER_MAXIMUM_LENGTH BETWEEN 1 AND 511
+    )
+    BEGIN
+        ALTER TABLE
+            config.installation_history
+        ALTER COLUMN
+            sql_server_version nvarchar(512) NOT NULL;
+
+        PRINT 'Widened config.installation_history.sql_server_version to nvarchar(512).';
+    END;
+END;
+GO
+
 /*
 Create view to show current installed version
 */
diff --git a/upgrades/2.4.1-to-2.4.2/01_widen_installation_history_sql_server_version.sql b/upgrades/2.4.1-to-2.4.2/01_widen_installation_history_sql_server_version.sql
new file mode 100644
index 0000000..726086f
--- /dev/null
+++ b/upgrades/2.4.1-to-2.4.2/01_widen_installation_history_sql_server_version.sql
@@ -0,0 +1,54 @@
+/*
+Copyright 2026 Darling Data, LLC
+https://www.erikdarling.com/
+
+Upgrade from 2.4.1 to 2.4.2
+Widen config.installation_history.sql_server_version from nvarchar(255) to nvarchar(512).
+Idempotent: safe to run multiple times.
+*/
+
+SET ANSI_NULLS ON;
+SET ANSI_PADDING ON;
+SET ANSI_WARNINGS ON;
+SET ARITHABORT ON;
+SET CONCAT_NULL_YIELDS_NULL ON;
+SET QUOTED_IDENTIFIER ON;
+SET NUMERIC_ROUNDABORT OFF;
+SET IMPLICIT_TRANSACTIONS OFF;
+SET STATISTICS TIME, IO OFF;
+GO
+
+USE PerformanceMonitor;
+GO
+
+IF OBJECT_ID(N'config.installation_history', N'U') IS NOT NULL
+BEGIN
+    IF EXISTS
+    (
+        SELECT
+            1
+        FROM INFORMATION_SCHEMA.COLUMNS
+        WHERE TABLE_SCHEMA = N'config'
+        AND   TABLE_NAME = N'installation_history'
+        AND   COLUMN_NAME = N'sql_server_version'
+        AND   DATA_TYPE = N'nvarchar'
+        AND   CHARACTER_MAXIMUM_LENGTH BETWEEN 1 AND 511
+    )
+    BEGIN
+        ALTER TABLE
+            config.installation_history
+        ALTER COLUMN
+            sql_server_version nvarchar(512) NOT NULL;
+
+        PRINT 'Widened config.installation_history.sql_server_version to nvarchar(512).';
+    END
+    ELSE
+    BEGIN
+        PRINT 'config.installation_history.sql_server_version already nvarchar(512) or wider; skipping.';
+    END;
+END
+ELSE
+BEGIN
+    PRINT 'Table config.installation_history does not exist; skipping.';
+END;
+GO
diff --git a/upgrades/2.4.1-to-2.4.2/upgrade.txt b/upgrades/2.4.1-to-2.4.2/upgrade.txt
new file mode 100644
index 0000000..85e6f31
--- /dev/null
+++ b/upgrades/2.4.1-to-2.4.2/upgrade.txt
@@ -0,0 +1 @@
+01_widen_installation_history_sql_server_version.sql