Microsoft SQL Server (Windows Authentication): unsupported ODBC connection params are now rejected

Retool now blocks Microsoft SQL Server resources that use Windows Authentication with custom ODBC connection parameters outside an approved allowlist. Previously, unsupported parameters were logged as warnings but still applied. They now cause resource setup to fail.

Who is affected

Self-hosted deployments using Microsoft SQL Server resources with Connect using Windows Auth enabled and one or more custom entries in Connection options (or equivalent resource JSON) whose keys are not on the allowlist. Windows Authentication is not available on Retool Cloud.

How to check if you are affected before upgrading

Search your Retool deployment logs (dbconnector / backend) for this exact string from the prior log-only release:

MSSQL Windows Auth ODBC connection string parameter not on allowlist

Each matching log line includes the parameter key (parameterKey in structured logs). Resources that logged this message will fail to connect or save after upgrading until those parameters are removed or replaced.

What you will see after upgrading

Resource setup or test connection fails with an error like:

Unsupported MSSQL ODBC connection string parameter "<key>". Only a fixed set of ODBC attributes may be supplied via connection params.

Remediation

1. Open each affected MSSQL Windows Auth resource.
2. Remove unsupported keys from paramsFromConnectionString.
3. Use Retool's built-in resource fields where possible. For example, use SSL/TLS for encryption and certificate verification.
4. If you need an ODBC attribute that is not listed below, contact Retool Support before upgrading.

Allowed paramsFromConnectionString keys

ODBC attribute	Alternate spellings accepted
APP	app
ApplicationIntent	applicationintent
ColumnEncryption	columnencryption
ConnectRetryCount	connectretrycount
ConnectRetryInterval	connectretryinterval
Connect Timeout	ConnectTimeout, connecttimeout
Failover_Partner	failoverpartner
FailoverPartnerSPN	failoverpartnerspn
HostnameInCertificate	hostnameincertificate
IpAddressPreference	ipaddresspreference
KeepAlive	keepalive
Language	language
LoginTimeout	logintimeout
MARS_Connection	marsconnection
MultiSubnetFailover	multisubnetfailover
Packet Size	PacketSize, packetsize
QueryLog_On	querylogon
QueryLogTime	querylogtime
Regional	regional
ServerSPN	serverspn, Server_SPN
Workstation ID	WorkstationID, workstationid
WSID	wsid

Security-sensitive attributes (Driver, Encrypt, Trusted_Connection, credentials, Server, Database, and similar) are set by Retool and cannot be supplied via connection params.

Common parameters that are blocked

• Encryption and certificate trust settings such as Encrypt and TrustServerCertificate — use the resource SSL/TLS settings instead.
• LoginRetryCount / LoginRetryInterval — use ConnectRetryCount / ConnectRetryInterval.
• Credential keys such as Uid, Pwd, User, or Password.
• Keys containing ; or crafted to inject additional ODBC attributes.