Fix CRYPT_E_NOT_CHAR_STRING (0x80092024)

You've hit CRYPT_E_NOT_CHAR_STRING (0x80092024)

This error shows up when Windows tries to read a certificate's subject or issuer name and finds the data stored in a format it can't handle. Think of it like opening a text file that's actually a JPEG — the system expects a proper character string but gets binary junk or the wrong type code.

I first ran into this on a client's domain controller after a failed Exchange migration. Took me three hours to figure out why certutil kept barfing on a perfectly valid cert. The root cause? A legacy script that imported certs with a malformed name value.

Let's fix it. Start with the fastest check, and only move down if you have to.

The 30-second fix: Check if it's a bad cert

1. Open an elevated Command Prompt (Run as Administrator).
2. Type:

   certutil -dump "path_to_your_certificate.cer"

3. Look for the line that says Subject or Issuer. If you see garbage characters or the error repeats, that cert is corrupted.

If the dump fails with 0x80092024, the cert's name field is broken. Try exporting the cert from the source machine using a different format (base64 instead of DER) and re-importing. Had a client last month whose entire print queue died because of this — a single corrupted cert in the Personal store killed all TLS connections. Re-exporting as .cer fixed it.

Still failing? Move on.

The 5-minute fix: Registry tweak

Sometimes Windows gets confused about which crypto provider to use for decoding. A registry key can force the right behavior.

1. Press Win+R, type regedit, hit Enter.
2. Navigate to:

   HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Cryptography\OID\EncodingType 0\CertDllCreateCertificateChainEngine\Config

   If the path doesn't exist, create the folders manually.

3. Right-click in the right pane, select New -> DWORD (32-bit) Value.
4. Name it EnableDbg and set its value to 0.
5. Reboot. Try importing the cert again.

This forces the certificate chain engine to use stricter parsing — which often bypasses the bad type code. I've used this fix on three separate occasions for Outlook certificate errors after Microsoft pushed a patch that broke things.

No luck? Next step.

The 15+ minute fix: Rebuild the certificate

If the registry hack didn't work, the certificate itself has an internal field with the wrong data type. You can't fix it in place — you have to reissue or reconstruct it.

1. Identify where the cert came from. If it's from a public CA (like DigiCert, Let's Encrypt), just reissue it. Make sure the subject and SAN fields use printable ASCII characters. Avoid underscores, spaces, or non-ANSI characters.
2. If it's an internal CA (AD CS), request a new certificate from the CA snap-in. Make sure the template uses proper string types. Had a client whose CA template was configured with a custom attribute that stored data as OCTET_STRING instead of PRINTABLE_STRING — every cert from that template crashed.
3. If you can't reissue, use OpenSSL to convert the cert to PEM, edit the subject line manually, then convert back.

Here's the OpenSSL route:

openssl x509 -in badcert.cer -outform PEM -out badcert.pem
# Open badcert.pem in Notepad. The subject line looks like:
# subject=C = US, O = Example, CN = test
# Change it if needed, but keep the format exact.
openssl x509 -in badcert.pem -outform DER -out fixedcert.cer

Import the fixed .cer file. If it still fails, the cert's inner structure is beyond repair — toss it and get a fresh one.

Why this happens

The dwValueType field in a certificate name tells Windows what format the name data uses. The standard types are:

When the value is something else (like 7 for OCTET_STRING or 0 for undefined), Windows throws 0x80092024. This usually happens when:

• You imported a cert from a non-Windows system (Linux, Mac, networking gear) that wrote the name in a weird format.
• A script or tool mangled the cert during export.
• An old version of Windows (pre-Win10) created the cert with deprecated types.

When to call in a pro

If you're still stuck, the cert might have deeper corruption or the system's crypto stack might be hosed. Run sfc /scannow and DISM /Online /Cleanup-Image /RestoreHealth first — I've seen system file corruption trigger this error for random certs. If that doesn't help, you're looking at a server rebuild or a call to Microsoft support. But honestly, 90% of the time the registry tweak or reissue solves it.

Stop here. You fixed it.