I have tried to run Shor's algorithm using IBM high performance simulator. I am currently using QuantumInstance to factorize a number. The code is provided below:

from qiskit import *

IBMQ.save_account('<My API String>')

from qiskit.tools.monitor import job_monitor
from qiskit.utils import QuantumInstance
from qiskit.algorithms import Shor

provider = IBMQ.get_provider('ibm-q')
sim = provider.backends.ibmq_qasm_simulator
quantum_instance = QuantumInstance(sim, shots=1024)
shor = Shor(quantum_instance=quantum_instance)
job_monitor(shor, interval=2)
rslt = shor.factor(N)
hsl = rslt.factors[0]
print("Factor result: "+str(hsl))

And it is giving me this error:

configrc.store_credentials:WARNING:2022-04-18 13:49:09,225: Credentials already present. Set overwrite=True to overwrite.
Traceback (most recent call last):
  File "C:\Users\LENOVO\AppData\Local\Programs\Python\Python310\lib\site-packages\qiskit\providers\ibmq\api\session.py", line 278, in request
  File "C:\Users\LENOVO\AppData\Local\Programs\Python\Python310\lib\site-packages\requests\models.py", line 960, in raise_for_status
    raise HTTPError(http_error_msg, response=self)
requests.exceptions.HTTPError: 401 Client Error: Unauthorized for url: https://auth.quantum-computing.ibm.com/api/users/loginWithToken

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "D:\Python\test_shor_2_cloud.py", line 4, in <module>
  File "C:\Users\LENOVO\AppData\Local\Programs\Python\Python310\lib\site-packages\qiskit\providers\ibmq\ibmqfactory.py", line 191, in load_account
    self._initialize_providers(credentials, preferences)
  File "C:\Users\LENOVO\AppData\Local\Programs\Python\Python310\lib\site-packages\qiskit\providers\ibmq\ibmqfactory.py", line 456, in _initialize_providers
    auth_client = AuthClient(credentials.token,
  File "C:\Users\LENOVO\AppData\Local\Programs\Python\Python310\lib\site-packages\qiskit\providers\ibmq\api\clients\auth.py", line 41, in __init__
    self.base_api = self._init_service_clients(**request_kwargs)
  File "C:\Users\LENOVO\AppData\Local\Programs\Python\Python310\lib\site-packages\qiskit\providers\ibmq\api\clients\auth.py", line 53, in _init_service_clients     
    access_token = self._request_access_token()
  File "C:\Users\LENOVO\AppData\Local\Programs\Python\Python310\lib\site-packages\qiskit\providers\ibmq\api\clients\auth.py", line 75, in _request_access_token     
    response = self.auth_api.login(self.api_token)
  File "C:\Users\LENOVO\AppData\Local\Programs\Python\Python310\lib\site-packages\qiskit\providers\ibmq\api\rest\root.py", line 125, in login
    return self.session.post(url, json={'apiToken': api_token}).json()
  File "C:\Users\LENOVO\AppData\Local\Programs\Python\Python310\lib\site-packages\requests\sessions.py", line 577, in post
    return self.request('POST', url, data=data, json=json, **kwargs)
  File "C:\Users\LENOVO\AppData\Local\Programs\Python\Python310\lib\site-packages\qiskit\providers\ibmq\api\session.py", line 300, in request
    raise RequestsApiError(message, status_code) from ex
qiskit.providers.ibmq.api.exceptions.RequestsApiError: '401 Client Error: Unauthorized for url: https://auth.quantum-computing.ibm.com/api/users/loginWithToken. Login failed., Error code: 3446.'

Any suggestion?

  • $\begingroup$ You can check those 2 posts, the issue looks similar to them 1 and 2 $\endgroup$
    – KMagdy
    Apr 18 at 8:26
  • $\begingroup$ Ahhh it's seems I don't force my save my API code... thanks for the links $\endgroup$
    – AFOEK
    Apr 19 at 6:17

1 Answer 1


You can run it on IBM circuit runner.Just execute the following code with your circuit.

    from qiskit import IBMQ

options = {
    'backend_name': 'ibmq_qasm_simulator'

runtime_inputs = {
    # A circuit or a list
  # of QuantumCircuits.
  'circuits': None, # [object,array] (required)
    # Whether to reset the qubits
  # to the ground state for
  # each shot.
  'init_qubits': None, # boolean
    # Initial position of virtual qubits
  # on physical qubits.
  'initial_layout': None, # [object,array]
    # Name of layout selection pass
  # ('trivial', 'dense', 'noise_adaptive', 'sabre')
  'layout_method': None, # string
    # Whether to apply measurement error
  # mitigation. Default is False.
  'measurement_error_mitigation': None, # boolean
    # How much optimization to perform
  # on the circuits (0-3). Higher
  # levels generate more optimized circuits.
  # Default is 1.
  'optimization_level': None, # integer
    # Delay between programs in seconds.
  'rep_delay': None, # number
    # Name of routing pass ('basic',
  # 'lookahead', 'stochastic', 'sabre').
  'routing_method': None, # string
    # Sets random seed for the
  # stochastic parts of the transpiler.
  'seed_transpiler': None, # integer
    # Number of repetitions of each
  # circuit, for sampling. Default: 1024.
  'shots': None, # integer
    # Name of translation pass ('unroller',
  # 'translator', 'synthesis').
  'translation_method': None, # string
    # Additional compilation options.
  'transpiler_options': None # object

provider = IBMQ.get_provider(

job = provider.runtime.run(

# Job id
# See job status

# Get results
result = job.result()
  • $\begingroup$ it's seems I cannot use circuit runner since I don't initialize my circuit but I use QuantumInstance for may shor algorithm $\endgroup$
    – AFOEK
    Apr 19 at 6:46

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