The Errors with configuration templates on Windows systems can be due to multiple causes, one of the most common being a misconfiguration in the certificates used by services such as Active Directory Federation Services (AD FS) or Web Application Proxy (WAP). These types of problems, commonly classified under the term «Windows template error», are often reflected in vague messages or a complete absence of clear error logs, making resolution difficult for system administrators or advanced users.
One of the most common causes of these errors is related to the Key Specification (KeySpec) parameter of the certificates. This property defines whether a private key can be used for signing, decryption, or both. Depending on the assigned value, attempts to establish secure connections using SSL/TLS or log in to pages protected by AD FS may fail. Issues related to Windows activation errors may also occur.
What causes the "windows template" error in certificates?
The KeySpec value determines the use of the key within systems that use the Microsoft Cryptographic API (CryptoAPI). An incorrect value can cause certificate validation failures, disrupting critical services. In older systems using traditional cryptographic providers (CSPs), valid values are:
- 1 (AT_KEYEXCHANGE): allows signing and encryption.
- 2 (AT_SIGNATURE): allows only signature.
In certificates generated with modern providers (CNG), this value will always be 0, since the separation between signature and encryption is not applied in its architecture.
The most common error arises when assigning a value of 2 to a certificate that is not exclusively for signing. For example, a certificate used to decrypt tokens in AD FS should be set to 1. Failure to do so may result in errors such as the inability to establish SSL connections or login issues, without explicit messages guiding the technician to the actual source of the problem. For more details on connection issues, you can read about how to troubleshoot reboot errors in Windows.
Consequences of the wrong KeySpec value
When KeySpec is not set correctly, the system may generate error events in the logs, such as event 67 in the AD FS trace, indicating, for example, a corrupted SSO cookie. This manifests itself in intermittent failures that, in many cases, leave no clear trace beyond low-level errors logged by SChannel or traces that aren't always actively monitored.
How to verify the KeySpec value in a certificate
To inspect the KeySpec value of a certificate, Microsoft recommends using the command-line tool certutil. Run certutil –v –store my provides a detailed view of the installed certificates. Within the CERT_KEY_PROV_INFO_PROP_ID block, you should review:
- ProviderType: Indicates whether this is a legacy certificate (value other than 0) or CNG (value 0).
- KeySpec: It should correspond to the purpose of the certificate.
The expected values for different types of AD FS certificates are shown below:
| Purpose of the Certificate | Valid KeySpec (Legacy CSP) | Valid KeySpec (CNG) |
|---|---|---|
| Service communication | 1 | N/A |
| Token Decryption | 1 | N/A |
| Token Signing | 1 or 2 | N/A |
| SSL | 1 | 0 |
Steps to correct the KeySpec value without issuing a new certificate
You do not need to request a new certificate to modify the KeySpec value. This can be adjusted by reimporting the certificate and its private key from a PFX file. The recommended steps are:
- Check and save the permissions of the current private key.
- Export the certificate and its key to a *.pfx file.
- On each server involved (AD FS or WAP):
- Remove the current certificate from the store.
- Open PowerShell with administrator privileges.
- Run:
certutil –importpfx certfile.pfx AT_KEYEXCHANGE - Enter the PFX password if requested.
- Check the private key permissions again.
- Restart the AD FS or WAP services as appropriate.
Other causes related to the "windows template" error
In addition to the KeySpec value, There are other configuration aspects that can cause errors in certificate requests. An example is the message: Error Parsing Request – The request subject name is invalid or too long, common when the subject's "Common Name" field exceeds the allowed limits (usually 64 characters).
This type of error may also be linked to the coincidence of the applicant's name with that of the certifying authority., which is not allowed by security policies. It is also possible that identity information was not included in the request, which also causes errors. To diagnose various errors, such as the inability to open JPG files in Windows, it is recommended to export the certificate request and inspect it with certutil -asn archivo.req.
Changing the length limits for relative distinguished names (RDNs) in Windows is possible through registry settings:
certutil -setreg ca\EnforceX500NameLengths 0This can be useful in environments where additional flexibility is required, although it should be noted that the common PKI standard sets strict limits that may be relevant in certain interoperability contexts.
Finally, to check if this restriction is active: certutil -getreg ca\EnforceX500NameLengths.
These types of issues are not always intuitive, as the error may appear without a visible message in the user interface. For example, a failure to authenticate through the WAP forms interface or AD FS could be due to these causes without any message being displayed, complicating diagnosis. Each error can be interconnected with other common Windows problems, so it's essential to understand their nature.
Errors related to "windows template" They are usually caused by incorrect configuration of key usage or certificate subject data. Thanks to tools like certutil With detailed knowledge of the parameters involved, it's possible to make precise adjustments to prevent these failures. Although they may seem like minor issues, they directly affect the reliability of critical systems, and their rapid resolution is vital to maintaining the security and stability of the Windows environment in corporate settings.
