# To verify a certificate
**URL:** https://community.blockcerts.org/t/to-verify-a-certificate/195
**Category:** Technical
**Created:** [June 30, 2017, 12:18am UTC](https://community.blockcerts.org/t/to-verify-a-certificate/195 "2017-06-30T00:18:11Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@Gabalo](https://community.blockcerts.org/u/Gabalo)
#### Post date: [June 30, 2017, 12:18am UTC](https://community.blockcerts.org/t/to-verify-a-certificate/195/1 "2017-06-30T00:18:12Z")
Hi,
I followed the README instructions step by step on Cert-Tools, Cert-Issuer and Cert-Viewer. I got to a point where I can see a certificate I created with my own roster.csv in my explorer with Cert-Viewer running.
But, I’m getting an error in the certificate screen when pressing the button “Verify certificate”. On the webpage nothing happens. On the cert-viewer terminal window I get the following error:
> ```
> 2017-06-29 17:57:24,975 - urllib3.connectionpool - DEBUG - Starting new HTTPS connection (1): www.blockcerts.org
> 2017-06-29 17:57:25,282 - urllib3.connectionpool - DEBUG - https://www.blockcerts.org:443 "GET /samples/2.0-alpha/revocationList.json HTTP/1.1" 200 289
> 2017-06-29 17:57:25,288 - root - DEBUG - Found results at url=https://www.blockcerts.org/samples/2.0-alpha/revocationList.json
> 2017-06-29 17:57:25,292 - urllib3.connectionpool - DEBUG - Starting new HTTP connection (1): api.blockcypher.com
> 2017-06-29 17:57:25,546 - urllib3.connectionpool - DEBUG - http://api.blockcypher.com:80 "GET /v1/btc/test3/txs/57d4e8e7b1807656f30908e1d8406e702f79def274fb15dc0237087a74cbcfa9?limit=100 HTTP/1.1" 404 100
> 2017-06-29 17:57:25,548 - root - ERROR - Error looking up transaction_id with url=http://api.blockcypher.com/v1/btc/test3/txs/57d4e8e7b1807656f30908e1d8406e702f79def274fb15dc0237087a74cbcfa9?limit=100, status_code=404
> 2017-06-29 17:57:25,548 - root - WARNING - Error looking up transaction, trying more connectors
> 2017-06-29 17:57:25,552 - urllib3.connectionpool - DEBUG - Starting new HTTPS connection (1): tbtc.blockr.io
> 2017-06-29 17:57:31,725 - urllib3.connectionpool - DEBUG - https://tbtc.blockr.io:443 "GET /api/v1/tx/info/57d4e8e7b1807656f30908e1d8406e702f79def274fb15dc0237087a74cbcfa9 HTTP/1.1" 404 None
> 2017-06-29 17:57:31,732 - root - ERROR - Error looking up transaction_id with url=https://tbtc.blockr.io/api/v1/tx/info/57d4e8e7b1807656f30908e1d8406e702f79def274fb15dc0237087a74cbcfa9, status_code=404
> 2017-06-29 17:57:31,733 - root - WARNING - Error looking up transaction, trying more connectors
> 2017-06-29 17:57:31,733 - root - ERROR - Unhandled Exception: [InvalidTransactionError(u'error looking up transaction_id=57d4e8e7b1807656f30908e1d8406e702f79def274fb15dc0237087a74cbcfa9',), InvalidTransactionError(u'error looking up transaction_id=57d4e8e7b1807656f30908e1d8406e702f79def274fb15dc0237087a74cbcfa9',)]
> Traceback (most recent call last):
> File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1612, in full_dispatch_request
> rv = self.dispatch_request()
> File "/usr/local/lib/python2.7/dist-packages/flask/app.py", line 1598, in dispatch_request
> return self.view_functions[rule.endpoint](**req.view_args)
> File "/usr/local/lib/python2.7/dist-packages/flask/views.py", line 84, in view
> return self.dispatch_request(*args, **kwargs)
> File "/home/gab/proyecto/cert-viewer/cert_viewer/views/verify_view.py", line 11, in dispatch_request
> view_model = self.view(*args, **kwargs)
> File "/home/gab/proyecto/cert-viewer/cert_viewer/verifier_bridge.py", line 8, in verify
> verify_response = verifier.verify_certificate(certificate)
> File "/usr/local/lib/python2.7/dist-packages/cert_verifier/verifier.py", line 28, in verify_certificate
> transaction_info = connector.lookup_tx(certificate_model.txid)
> File "/usr/local/lib/python2.7/dist-packages/cert_verifier/connectors.py", line 71, in lookup_tx
> raise InvalidTransactionError(exceptions)
> InvalidTransactionError: [InvalidTransactionError(u'error looking up transaction_id=57d4e8e7b1807656f30908e1d8406e702f79def274fb15dc0237087a74cbcfa9',), InvalidTransactionError(u'error looking up transaction_id=57d4e8e7b1807656f30908e1d8406e702f79def274fb15dc0237087a74cbcfa9',)]
>
> ```
Now, if I try to access that link by myself ([https://tbtc.blockr.io/api/v1/tx/info/57d4e8e7b1807656f30908e1d8406e702f79def274fb15dc0237087a74cbcfa9](https://tbtc.blockr.io/api/v1/tx/info/57d4e8e7b1807656f30908e1d8406e702f79def274fb15dc0237087a74cbcfa9)) I get the following error:
> {“status”:“fail”,“data”:null,“code”:404,“message”:“No records found”}
Seems like my certificate wasn’t ‘uploaded’ or something?
Hope you can clarify this to me.
Thanks!
Gabriel
---
### Author:  [@kim](https://community.blockcerts.org/u/kim)
#### Post date: [July 3, 2017, 6:52pm UTC](https://community.blockcerts.org/t/to-verify-a-certificate/195/2 "2017-07-03T18:52:47Z")
Hi Gabriel,
I’m wondering – did you use the docker image of cert-issuer to issue the certificates? The docs may have been unclear. The default mode of the docker image is `regtest`, which is a test mode that doesn’t issue to a blockchain. You need to issue either in `testnet` or `mainnet` mode to be able to use the verifier.
If this is the case (if you used `regtest` mode), then you will only be able to view the certificate. So you probably did this correctly. I will find a way to clarify the docs, because I think this is unclear right now.
Thanks,
Kim
---
### Author:  [@Gabalo](https://community.blockcerts.org/u/Gabalo)
#### Post date: [July 3, 2017, 7:20pm UTC](https://community.blockcerts.org/t/to-verify-a-certificate/195/3 "2017-07-03T19:20:20Z")
Thank you for your answer Kim.
Indeed I was using the docker image. I found some documents about the issuing options for Testnet mode. They clarify some more, I’ll try to run on Testnet mode following the instructions there.
[https://github.com/blockchain-certificates/cert-issuer/blob/master/docs/bitcoin\_options.md](https://github.com/blockchain-certificates/cert-issuer/blob/master/docs/bitcoin_options.md)
[https://github.com/blockchain-certificates/cert-issuer/blob/master/docs/issuing.md](https://github.com/blockchain-certificates/cert-issuer/blob/master/docs/issuing.md)
I have a question though. At some point the second document mentions a transaction fee of 60,000 satoshis (~$1.50 USD, 7/3/2017). Is this fee always needed, even when working on Testnet mode?
Regards,
Gabriel
---
### Author:  [@kim](https://community.blockcerts.org/u/kim)
#### Post date: [July 9, 2017, 10:08pm UTC](https://community.blockcerts.org/t/to-verify-a-certificate/195/4 "2017-07-09T22:08:51Z")
A fee is always recommended, even in testnet mode, to ensure faster mining of the transaction. There are many testnet faucets you can use to get some funds.