I have been using Qiskit over the last few weeks to run different programs. But right now, whenever I try to run any code, it gives me a 403 error stating that I am out of credits. I am creating a random walk simulation.

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    $\begingroup$ Hi Rahif. Welcome to QCSE. Please finish your thought - what are you asking? What programs are you running? What system? etc. Otherwise, this question should be closed, as it is unclear what you are asking. Thanks! $\endgroup$ Jun 24, 2019 at 23:07
  • $\begingroup$ 403 means a bad or no password. It looks to me more like a network configuration or registration problem. $\endgroup$
    – peterh
    Jun 25, 2019 at 22:03

1 Answer 1


The 403 error is a http error - Forbidden. It's comming from the server that is giving you access to the quantum computer, not from the quantum computer its self.

If you are using IBM Q Experience you shuld check out the FAQ page. Regarding to credits it states:

A User has a maximum of 15 credits, and these credits are replenished upon the greater of 24 hours or when your execution has run off the queue.

So you have probably consumed your allocated credits and the http server is rejecting your requests.

  • $\begingroup$ I am getting this error even though I have used the token created from quantum-computing.ibm.com/account & this is my first request to melbourne qcomp =provider.get_backend('ibmq_16_melbourne').. I really doubt that I have exhausted the limit of my request... 403 looks like some thing is missing from authorization perspective... do I need to setup anything else to make this working from Jupyter notebook running on my machine $\endgroup$ Dec 11, 2019 at 7:03

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