# Error with cert-verifier

**URL:** https://community.blockcerts.org/t/error-with-cert-verifier/3249
**Category:** Technical
**Created:** [July 10, 2022, 5:46am UTC](https://community.blockcerts.org/t/error-with-cert-verifier/3249 "2022-07-10T05:46:40Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![Tomi](https://avatars.discourse-cdn.com/v4/letter/t/f4b2a3/32.png) [@Tomi](https://community.blockcerts.org/u/Tomi)
#### Post date: [July 10, 2022, 5:46am UTC](https://community.blockcerts.org/t/error-with-cert-verifier/3249/1 "2022-07-10T05:46:40Z")

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I executed cert-issuer with unsighned\_certificate and got a blockchain\_certificate, so I tried cert-verifier to verify my blockchain\_certificate, but I got this error

**cert\_core.UnknownBlockcertVersionException**

 ![スクリーンショット (793)](https://us1.discourse-cdn.com/flex016/uploads/blockcerts/original/1X/75b1f8f4c82a3ae6e098dae01c0a258c68112ebf.png)

Anyone can help this??

**unsighned\_certificate**  
{  
“@context”: [  
“[https://www.w3.org/2018/credentials/v1](https://www.w3.org/2018/credentials/v1)”,  
{  
“alumniOf”: {  
“@id”: “[alumniOf - Schema.org Property](http://schema.org/alumniOf)”,  
“@type”: “[http://www.w3.org/1999/02/22-rdf-syntax-ns#HTML](http://www.w3.org/1999/02/22-rdf-syntax-ns#HTML)”  
}  
},  
“[https://w3id.org/blockcerts/v3](https://w3id.org/blockcerts/v3)”  
],  
“id”: “urn:uuid:bbba8553-8ec1-445f-82c9-a57251dd731c”,  
“type”: [  
“VerifiableCredential”,  
“BlockcertsCredential”  
],  
“issuer”: “did:example:23adb1f712ebc6f1c276eba4dfa”,  
“issuanceDate”: “2022-01-01T19:33:24Z”,  
“credentialSubject”: {  
“id”: “did:example:ebfeb1f712ebc6f1c276e12ec21”,  
“alumniOf”: {  
“id”: “did:example:c276e12ec21ebfeb1f712ebc6f1”  
}  
}  
}

**blockchain\_certificate**  
{“@context”: [“[https://www.w3.org/2018/credentials/v1](https://www.w3.org/2018/credentials/v1)”, {“alumniOf”: {“@id”: “[alumniOf - Schema.org Property](http://schema.org/alumniOf)”, “@type”: “[http://www.w3.org/1999/02/22-rdf-syntax-ns#HTML](http://www.w3.org/1999/02/22-rdf-syntax-ns#HTML)”}}, “[https://w3id.org/blockcerts/v3](https://w3id.org/blockcerts/v3)”], “id”: “urn:uuid:bbba8553-8ec1-445f-82c9-a57251dd731c”, “type”: [“VerifiableCredential”, “BlockcertsCredential”], “issuer”: “did:example:23adb1f712ebc6f1c276eba4dfa”, “issuanceDate”: “2022-01-01T19:33:24Z”, “credentialSubject”: {“id”: “did:example:ebfeb1f712ebc6f1c276e12ec21”, “alumniOf”: {“id”: “did:example:c276e12ec21ebfeb1f712ebc6f1”}}, “proof”: {“type”: “MerkleProof2019”, “created”: “2022-07-10T14:42:39.560411”, “proofValue”: “zMcm4LfQFUZkWZxsDRz3yhkRgM24ZG2M9EFRxhEsrgHDxohmrk1nbhnfwXMKawnRZAfiZuFs34GroEWma5UZi2gqAQvArwRFYhbQqqMgEJWj6NpSpE8o97FuQBPiRLhQRWUpoh1aVu2nyvSTmW2JfAY5nrHekag6Vv7wrLinUEj8D2PiLcGa5SUBVc6yFb7keuTD4MSFTQdBCc4xgpyCi2dho8nPMSSNVQrFUa2pWbL2vEdiEzfkwnELvYaadZNDA1sfJHxpThzZsTZJZ18GBWQLDe6fVrWkmfQgzPLpvBHQaCBUa5s”, “proofPurpose”: “assertionMethod”, “verificationMethod”: “did:key:z6Mkkxadrz78Zbw2NAABLmUq4JJv838hg2BDQ45buoSETGVG”}}

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<div class="post-metadata">

### Author: ![lemoustachiste](https://avatars.discourse-cdn.com/v4/letter/l/7c8e57/32.png) [@lemoustachiste](https://community.blockcerts.org/u/lemoustachiste)
#### Post date: [July 11, 2022, 1:42pm UTC](https://community.blockcerts.org/t/error-with-cert-verifier/3249/2 "2022-07-11T13:42:31Z")

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Yeah, the python `cert-verifier` library has not been maintained in very long, if not deprecated.  
To verify your cert you should use `cert-verifier-js` which you can run on node [GitHub - blockchain-certificates/cert-verifier-js: Javascript library for verifying Blockcerts Certificates](https://github.com/blockchain-certificates/cert-verifier-js). There is an example here: [cert-verifier-js/server.js at master · blockchain-certificates/cert-verifier-js · GitHub](https://github.com/blockchain-certificates/cert-verifier-js/blob/master/test/manual-testing/node/server.js)

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<div class="post-metadata">

### Author: ![Tomi](https://avatars.discourse-cdn.com/v4/letter/t/f4b2a3/32.png) [@Tomi](https://community.blockcerts.org/u/Tomi)
#### Post date: [July 13, 2022, 11:42pm UTC](https://community.blockcerts.org/t/error-with-cert-verifier/3249/3 "2022-07-13T23:42:50Z")

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Ah I see. I’ll try it! Thanks