RPC_S_INVALID_STRING_UUID - 1705 (0x6A9)
The string universal unique identifier (UUID) is invalid.
Updated: Feb 21, 2026
Technical Background
The error code RPC_S_INVALID_STRING_UUID is a specific return value from the Remote Procedure Call (RPC) API in Windows. This error indicates that a string representation of a Universal Unique Identifier (UUID) passed to an RPC function was not valid.
Error Details
Numeric Code and Hexadecimal Representation
- Numeric Code: 1705
- Hexadecimal Code: 0x6A9
Short Description
The string universal unique identifier (UUID) is invalid. This error typically occurs when an application attempts to use a UUID in an RPC call, but the provided string does not conform to the expected format.
Common Causes
This error can be caused by several factors:
- Invalid Parameter Values: The UUID passed as a parameter may contain characters or formats that are not recognized by the RPC API.
- Incorrect Object Type: The operation being performed is expecting a different type of identifier, such as an integer or hexadecimal value, rather than a string representation of a UUID.
Real-World Context
In the context of Windows applications utilizing the RPC API, this error can occur when attempting to register or unregister services, or when performing operations that require valid UUIDs. For example, if an application is trying to use a UUID in a registration request and the string does not match the expected format, this error will be returned.
Is This Error Critical?
The criticality of this error depends on the specific operation being performed. If the operation involves registering or unregistering services, it may prevent the service from functioning correctly. However, if the operation is less critical, such as a background task, the impact might be minimal.
How to Diagnose
To diagnose and resolve RPC_S_INVALID_STRING_UUID, follow these steps:
- Review Operation Context: Ensure that the UUID being used in the RPC call is appropriate for the operation being performed.
- Validate Parameters: Check the format of the string UUID. It should match the standard UUID format, which consists of 32 hexadecimal digits divided into five groups separated by hyphens (e.g.,
123e4567-e89b-12d3-a456-426614174000). - Confirm Object Types: Verify that the operation is expecting a string UUID and not another type of identifier.
How to Resolve
To resolve this error, ensure that the UUID passed as a parameter is valid and correctly formatted. Here are some practical steps:
- Correct any invalid characters in the UUID string.
- Ensure that the UUID format matches the expected standard.
- Retry the operation with a valid UUID.
Developer Notes
When working with RPC APIs, it is crucial to validate all parameters, especially those representing identifiers like UUIDs. Ensuring that these values are correctly formatted can prevent such errors and improve application reliability.
Related Errors
RPC_S_UUID_NO_ADDRESS(1704): Indicates an invalid or unsupported UUID address.RPC_S_INVALID_BINDING(1723): Occurs when the binding information is not valid for the RPC call.
FAQ
Q: What does RPC_S_INVALID_STRING_UUID mean?
A: It indicates that a string representation of a Universal Unique Identifier (UUID) passed to an RPC function was not valid.
Q: How can I prevent this error from occurring?
A: Ensure that the UUIDs used in your application are correctly formatted and appropriate for the operation being performed. Validate all parameters before making RPC calls.
Q: Can this error affect system stability?
A: Generally, no. However, if critical services or operations are impacted, it could lead to system instability or service failures.
Summary
The RPC_S_INVALID_STRING_UUID error code is a specific return value from the Windows RPC API indicating that an invalid string UUID was passed as a parameter. Ensuring proper validation and formatting of UUIDs can help prevent this error and maintain application reliability.