ERROR_CS_ENCRYPTION_INVALID_SERVER_RESPONSE - 6017 (0x1781)
The remote server sent an invalid response for a file being opened with Client Side Encryption.
Updated: Feb 21, 2026
Technical Meaning
This error code, ERROR_CS_ENCRYPTION_INVALID_SERVER_RESPONSE (6017 or 0x1781), is returned when a file operation involving Client Side Encryption (CSE) fails due to an invalid response from the remote server. This typically occurs during operations such as opening a CSE-protected file over a network.
Error Details
The error signifies that the client-side encryption mechanism expected a specific type of response from the server, but received one that was deemed invalid or unexpected. This can occur in scenarios where the client and server do not have compatible encryption configurations or if there is an issue with the communication between them.
Usage Context
This error code is relevant to operations involving Client Side Encryption (CSE) on Windows systems. CSE allows files to be encrypted locally before being sent over a network, ensuring that sensitive data remains protected even when it is transmitted across untrusted networks.
Developer Interpretation
When encountering this error, developers should consider the following:
- Verify that both the client and server are using compatible encryption algorithms and key lengths.
- Ensure that the network connection between the client and server is stable and secure.
- Check for any recent changes or updates to the encryption configuration on either side of the communication.
Related Errors
ERROR_CS_ENCRYPTION_INVALID_METADATA_PROTECTION(6018)ERROR_CS_ENCRYPTION_UNSUPPORTED_SERVER(6023)ERROR_CS_ENCRYPTION_FAILURE(6019)
FAQ
Q: What does the error code 6017 mean?
A: The error code 6017, ERROR_CS_ENCRYPTION_INVALID_SERVER_RESPONSE, indicates that an invalid response was received from a remote server during a Client Side Encryption operation.
Q: How can I resolve this issue?
A: Ensure that both the client and server are using compatible encryption settings. Verify network connectivity and check for any recent changes to the encryption configuration.
Summary
The ERROR_CS_ENCRYPTION_INVALID_SERVER_RESPONSE error code (6017) is a specific technical indicator used by Windows systems when Client Side Encryption operations fail due to an invalid response from a remote server. Developers should focus on ensuring compatibility and stability in their networked encryption scenarios.