# HTTPError: 404 Client Error: Is there anything I can do about this? **URL:** \ **Category:** API\ **Tags:** api, c3s\ **Created:** [9 June 2021 08:19 UTC](https://forum.ecmwf.int/t/httperror-404-client-error-is-there-anything-i-can-do-about-this/1472 "2021-06-09T08:19:37Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![Petri\_Clusius](https://forum.ecmwf.int/letter_avatar_proxy/v4/letter/p/50afbb/32.png) [@Petri\_Clusius](https://forum.ecmwf.int/u/Petri_Clusius)\ **Post date:** [9 June 2021 08:19 UTC](https://forum.ecmwf.int/t/httperror-404-client-error-is-there-anything-i-can-do-about-this/1472/1 "2021-06-09T08:19:37Z")
Hello everyone, we are experiencing problems with mars retrieval, in essence the error is: requests.exceptions.HTTPError: 404 Client Error: for url: [https://cds.climate.copernicus.eu/api/v2/resources/reanalysis-era5-single-levels](https://cds.climate.copernicus.eu/api/v2/resources/reanalysis-era5-single-levels) I will include a more detailed error output in the end. This error started today with all my requests, after they had been working for some days after the last mars problem got fixed during the weekend. So nothing except date had changed in the way the requests had been parsed (by flex\_extract). Anyone know if this is a mars issue again, or some problem I could take care on my side? My colleague is having exact same problem with his similar configuration, neither of us have changed anything but date of the requested data. I have checked that .cdsapirc file is in order, I have also defined the CDS\_API\_KEY and CDS\_API\_URL env variables with the key and url. So the way my CDS credentials are stored and accessed locally hasn't changed at all between the working and non working condition. Any help is appreciated! - Petri The request and the following error messages from the retrieval: > ``` > ... > marsclass: EA > dataset: None > type: FC > levtype: SFC > levelist: 1 > repres: > date: 20180612/to/20180612 > resol: 399 > stream: OPER > area: 85.0/-80.0/21.0/70.0 > time: 06/18 > step: 1/to/12/by/1 > expver: 1 > number: OFF > accuracy: 24 > grid: 0.5/0.5 > gaussian: > target: /scratch/project_2004394/GRIB_E5/20180613/FCOG_acc_SL.20180612.114870.114871.grb > param: 142.128/143.128/146.128/180.128/181.128/176.128 > target: /scratch/project_2004394/GRIB_E5/20180613/FCOG_acc_SL.20180612.114870.114871.grb > RETRIEVE ERA5 WITH CDS API! > /appl/soft/ai/miniconda3/envs/python-data-3.7.3-1/lib/python3.7/site-packages/urllib3/connectionpool.py:847: InsecureRequestWarning: Unverified HTTPS request is being made. Adding certificate verification is strongly advised. See:[https://urllib3.readthedocs.io/en/latest/advanced-usage.html#ssl-warnings](https://urllib3.readthedocs.io/en/latest/advanced-usage.html#ssl-warnings) > InsecureRequestWarning) > 2021-06-09 11:32:04,240 INFO Welcome to the CDS > 2021-06-09 11:32:04,240 INFO Sending request to[https://cds.climate.copernicus.eu/api/v2/resources/reanalysis-era5-single-levels](https://cds.climate.copernicus.eu/api/v2/resources/reanalysis-era5-single-levels) > /appl/soft/ai/miniconda3/envs/python-data-3.7.3-1/lib/python3.7/site-packages/urllib3/connectionpool.py:847: InsecureRequestWarning: Unverified HTTPS request is being made. Adding certificate verification is strongly advised. See:[https://urllib3.readthedocs.io/en/latest/advanced-usage.html#ssl-warnings](https://urllib3.readthedocs.io/en/latest/advanced-usage.html#ssl-warnings) > InsecureRequestWarning) > > MARS Request failed! > > Resource reanalysis-era5-single-levels not found > Traceback (most recent call last): > File "~/.local/lib/python3.7/site-packages/cdsapi/api.py", line 427, in _api > result.raise_for_status() > File "/appl/soft/ai/miniconda3/envs/python-data-3.7.3-1/lib/python3.7/site-packages/requests/models.py", line 940, in raise_for_status > raise HTTPError(http_error_msg, response=self) > requests.exceptions.HTTPError: 404 Client Error: for url:[https://cds.climate.copernicus.eu/api/v2/resources/reanalysis-era5-single-levels](https://cds.climate.copernicus.eu/api/v2/resources/reanalysis-era5-single-levels) > > During handling of the above exception, another exception occurred: > > Traceback (most recent call last): > File "~/flex_extract_v7.1.2/Source/Python/Classes/MarsRetrieval.py", line 592, in data_retrieve > attrs, target) > File "~/.local/lib/python3.7/site-packages/cdsapi/api.py", line 348, in retrieve > result = self._api("%s/resources/%s" % (self.url, name), request, "POST") > File "~/.local/lib/python3.7/site-packages/cdsapi/api.py", line 450, in _api > raise Exception(error) > Exception: Resource reanalysis-era5-single-levels not found > ``` ---
**Author:** ![Petri\_Clusius](https://forum.ecmwf.int/letter_avatar_proxy/v4/letter/p/50afbb/32.png) [@Petri\_Clusius](https://forum.ecmwf.int/u/Petri_Clusius)\ **Post date:** [9 June 2021 09:05 UTC](https://forum.ecmwf.int/t/httperror-404-client-error-is-there-anything-i-can-do-about-this/1472/2 "2021-06-09T09:05:03Z")
Just saw the recent announcement; apparently this issue is being worked on.