---
title: "Database Engine: Breaking Changes"
titleSuffix: SQL Server 2025
description: Breaking changes to database engine features in SQL Server 2025.
author: MikeRayMSFT
ms.author: mikeray
ms.reviewer: randolphwest, mathoma
ms.date: 01/12/2026
ms.service: sql
ms.subservice: release-landing
ms.topic: troubleshooting-general
ms.custom:
  - ignite-2025
helpviewer_keywords:
  - "breaking changes 2017 [SQL Server]"
monikerRange: ">=sql-server-2017 || >=sql-server-linux-2017"
---
# Breaking changes to Database Engine features in SQL Server 2025

[!INCLUDE [sqlserver2025](../includes/applies-to-version/sqlserver2025.md)]

This article describes the breaking changes to features in the SQL Server Database Engine introduced with [!INCLUDE [sssql25-md](../includes/sssql25-md.md)]. These changes can break applications, scripts, or functionalities that are based on earlier versions of [!INCLUDE [ssNoVersion](../includes/ssnoversion-md.md)].

## Linked server connections fail after an upgrade

[!INCLUDE [sssql25-md](../includes/sssql25-md.md)] includes changes to [encryption](../relational-databases/security/networking/tds-8.md) that introduce a breaking change to [linked servers](../relational-databases/linked-servers/linked-servers-database-engine.md#sql-server-2025-and-msoledbsql-version-19). These changes can break applications, scripts, or functionalities that are based on earlier versions of [!INCLUDE [ssNoVersion](../includes/ssnoversion-md.md)].

When you upgrade from previous versions of SQL Server to [!INCLUDE [sssql25-md](../includes/sssql25-md.md)] with Microsoft OLE DB Driver 19, existing linked server configurations might fail. Different default values for the encryption parameter might cause this failure unless a valid certificate is provided.

In [!INCLUDE [sssql25-md](../includes/sssql25-md.md)]:

- [Linked servers to instances of SQL Server 2025 must use the `Encrypt` parameter in the connection string](../relational-databases/linked-servers/linked-servers-database-engine.md#sql-server-2025-and-msoledbsql-version-19)
- [When you migrate from previous editions of SQL Server to SQL Server 2025 with Microsoft OLE DB Driver 19, existing linked server configurations can fail](../relational-databases/linked-servers/linked-servers-database-engine.md#updating-from-previous-oledb-versions)

For information about how to connect securely to [!INCLUDE [sssql25-md](../includes/sssql25-md.md)] instances, see [TDS 8.0](../relational-databases/security/networking/tds-8.md).

## Replication components fail after an upgrade

[!INCLUDE [sssql25-md](../includes/sssql25-md.md)] includes changes to [encryption](../relational-databases/security/networking/tds-8.md) that introduce a breaking change to [Transactional](../relational-databases/replication/transactional/transactional-replication.md#configure-tls-13-encryption), [Snapshot](../relational-databases/replication/snapshot-replication.md#configure-tls-13-encryption), [Peer-to-peer](../relational-databases/replication/transactional/peer-to-peer-transactional-replication.md#configure-tls-13-encryption), and [Merge](../relational-databases/replication/merge/merge-replication.md#configure-tls-13-encryption) replication.

Replication components might fail after an upgrade to [!INCLUDE [sssql25-md](../includes/sssql25-md.md)] from all previous versions of SQL Server, if your SQL Server instance:

- Is configured as a replication publisher.
- Has a remote distributor in the replication topology.
- Isn't configured with a trusted certificate.

You might see the following behavior after the upgrade:

- Replication continues to succeed but changes to the publication fail.
- Replication Monitor in SQL Server Management Studio (SSMS) fails.
- Agent status in the SSMS UI fails.

A remote distributor uses a linked server for communication between the publisher and distributor. The secure default introduced in [!INCLUDE [sssql25-md](../includes/sssql25-md.md)] of the OLEDB 19 provider requires that `TrustServerCertificate=False`.

You can resolve this issue preemptively before you start the upgrade, or you can resolve the issue if replication components fail after an upgrade.

### Before starting the upgrade

If you know that your SQL Server instance is going to encounter this issue after an upgrade, you can preemptively mitigate the failure by configuring the SQL Server instance to use a [public commercial certificate](configure-windows/special-cases-for-encrypting-connections-sql-server.md#use-a-certificate-issued-by-a-public-commercial-certificate-authority-and-only-some-clients-need-encrypted-connections) or a certificate from an [internal certificate authority](configure-windows/special-cases-for-encrypting-connections-sql-server.md#use-a-certificate-issued-by-an-internal-ca-or-created-by-using-new-selfsignedcertificate-or-makecert).

This is the recommended option for maximum security.

### Failed components after an upgrade

If your replication components fail after an upgrade, you can still configure the SQL Server instance to use a [public commercial certificate](configure-windows/special-cases-for-encrypting-connections-sql-server.md#use-a-certificate-issued-by-a-public-commercial-certificate-authority-and-only-some-clients-need-encrypted-connections) or a certificate from an [internal certificate authority](configure-windows/special-cases-for-encrypting-connections-sql-server.md#use-a-certificate-issued-by-an-internal-ca-or-created-by-using-new-selfsignedcertificate-or-makecert).

Alternatively, you can choose the less secure option to override the secure default of the OLEDB 19 provider and set `trust_distributor_certificate=yes` so the distributor trusts the self-signed certificate.

To override the new secure default, use the [sp_changedistributor_property](../relational-databases/system-stored-procedures/sp-changedistributor-property-transact-sql.md) stored procedure to set the `trust_distributor_certificate` option to `yes`:

```sql
EXECUTE sp_changedistributor_property
    @property = N'trust_distributor_certificate',
    @value = N'yes';
```

[!INCLUDE [sql-25-repl-distributor-info](../includes/sql-25-repl-distributor-info.md)]

## Adding a remote replication distributor fails

[!INCLUDE [sssql25-md](../includes/sssql25-md.md)] includes changes to [encryption](../relational-databases/security/networking/tds-8.md) that introduce a breaking change to [Transactional](../relational-databases/replication/transactional/transactional-replication.md#configure-tls-13-encryption), [Snapshot](../relational-databases/replication/snapshot-replication.md#configure-tls-13-encryption), [Peer-to-peer](../relational-databases/replication/transactional/peer-to-peer-transactional-replication.md#configure-tls-13-encryption), and [Merge](../relational-databases/replication/merge/merge-replication.md#configure-tls-13-encryption) replication.

When configuring a distributor for replication, the [sp_adddistributor](../relational-databases/system-stored-procedures/sp-adddistributor-transact-sql.md) stored procedure fails when:

- The publisher is a [!INCLUDE [sssql25-md](../includes/sssql25-md.md)] instance.
- The distributor is remote.
- The distributor isn't configured with a trusted certificate.

You might see the following error when running `sp_adddistributor` on the publisher instance:

```error-text
OLE DB provider "MSOLEDBSQL19" for linked server "repl_distributor" returned message
"Client unable to establish connection".
Msg -2146893019, Level 16, State 1, Line 21
SSL Provider: The certificate chain was issued by an authority that is not trusted.
```

A remote distributor uses a linked server for communication between the publisher and distributor. The secure default introduced in [!INCLUDE [sssql25-md](../includes/sssql25-md.md)] of the OLEDB 19 provider requires that `TrustServerCertificate=False`.

To resolve this issue, configure the distributor SQL Server instance to use a [public commercial certificate](configure-windows/special-cases-for-encrypting-connections-sql-server.md#use-a-certificate-issued-by-a-public-commercial-certificate-authority-and-only-some-clients-need-encrypted-connections) or a certificate from an [internal certificate authority](configure-windows/special-cases-for-encrypting-connections-sql-server.md#use-a-certificate-issued-by-an-internal-ca-or-created-by-using-new-selfsignedcertificate-or-makecert).

Alternatively, you can choose the less secure option to override the secure default of the OLEDB 19 provider and set `TrustServerCertificate=True` so the distributor trusts the self-signed certificate. To override the default, use the `trust_distributor_certificate` parameter when calling the [sp_adddistributor](../relational-databases/system-stored-procedures/sp-adddistributor-transact-sql.md) stored procedure:

```sql
EXECUTE sys.sp_adddistributor @trust_distributor_certificate = 'yes';
```

[!INCLUDE [sql-25-repl-distributor-info](../includes/sql-25-repl-distributor-info.md)]

## Remote log shipping monitoring can break

[!INCLUDE [sssql25-md](../includes/sssql25-md.md)] includes changes to [encryption](../relational-databases/security/networking/tds-8.md) that introduce a breaking change to [log shipping](log-shipping/about-log-shipping-sql-server.md#enforce-tls-13-encryption). You might encounter these issues when you upgrade.

Log shipping monitoring can break if the monitor is a remote [!INCLUDE [sssql25-md](../includes/sssql25-md.md)] instance when other SQL Server instances in the log shipping topology use a previous version.

For information about how to connect securely to [!INCLUDE [sssql25-md](../includes/sssql25-md.md)] instances, see [TDS 8.0](../relational-databases/security/networking/tds-8.md).

## Full-Text queries and populations fail after upgrade

[!INCLUDE [sssql25-md](../includes/sssql25-md.md)] removes all legacy word breaker and filter binaries used by [Full-Text Search](../relational-databases/search/full-text-search.md). These components are rebuilt with a modern toolset and offer expanded support for more languages and document types. For more information, see [Behavior changes in Full-Text Search](../relational-databases/search/behavior-changes-full-text-search.md). Existing indexes after upgrade are designated with `index_version = 1` as per [sys.fulltext_indexes](../relational-databases/system-catalog-views/sys-fulltext-indexes-transact-sql.md). Newly created indexes are version 2 and use the new components, unless you specify otherwise by using the [FULLTEXT_INDEX_VERSION](../t-sql/statements/alter-database-scoped-configuration-transact-sql.md#fulltext_index_version) database scoped configuration.

Any Full-Text query on a version 1 index fails to find the word breaker binaries on disk immediately after upgrade:

```output
Msg 30010, Level 16, State 2, Line 8
An error has occurred during the full-text query. Common causes include: word-breaking errors or timeout, FDHOST permissions/ACL issues, service account missing privileges, malfunctioning IFilters, communication channel issues with FDHost and sqlservr.exe, etc. If recently performed in-place upgrade to SQL2025, For help please see https://aka.ms/sqlfulltext.
```

Similarly, any Full-Text population on a version 1 index fails to find the filter binaries on disk after upgrade:

```output
Warning: No appropriate filter was found during full-text index population for table or indexed view '[db].[dbo].[table_name]' (table or indexed view ID '901578250', database ID '5'), full-text key value '1'. Some columns of the row were not indexed.
```

### Rebuild existing indexes with new version

Rebuild your indexes to use version 2 components.

```sql
-- Verify value = 2
SELECT *
FROM sys.database_scoped_configurations
WHERE [name] = 'FULLTEXT_INDEX_VERSION';

-- Per catalog upgrade
ALTER FULLTEXT CATALOG [FtCatalog] REBUILD;
```

To upgrade individual indexes without rebuilding the entire catalog, drop and recreate the indexes.

### Keep using version 1

> [!IMPORTANT]  
> Version 1 is deprecated for [!INCLUDE [ssnoversion-md](../includes/ssnoversion-md.md)] on Linux. In [!INCLUDE [sssql25-md](../includes/sssql25-md.md)] and later versions, the `mssql-server-fts` package doesn't include version 1 binaries. Attempting to install mismatched versions of the `mssql-server-fts` and `mssql-server` packages is unsupported, and results in full-text failures.

If you need to use version 1 for application compatibility, first set `FULLTEXT_INDEX_VERSION = 1` to avoid an unintended upgrade on rebuild.

```sql
ALTER DATABASE SCOPED CONFIGURATION
    SET FULLTEXT_INDEX_VERSION = 1;
```

Next, copy the legacy word breaker and filter binaries from an older instance to the target instance's `Binn` folder.

## Related content

- [TDS 8.0](../relational-databases/security/networking/tds-8.md)
- [Deprecated Database Engine features in SQL Server 2019 (15.x)](deprecated-database-engine-features-in-sql-server-2019.md)
- [Discontinued Database Engine functionality in SQL Server](discontinued-database-engine-functionality-in-sql-server.md)