# Title: CDS ERA5 requests rejected despite sequential Python script - workaround?

**URL:** <https://forum.croco-ocean.org/t/title-cds-era5-requests-rejected-despite-sequential-python-script-workaround/7711>\
**Category:** croco tools (pre/post-processing)\
**Tags:** forcing\
**Created:** [November 13, 2026, 4:52am UTC](https://forum.croco-ocean.org/t/title-cds-era5-requests-rejected-despite-sequential-python-script-workaround/7711 "2026-11-13T04:52:13Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![AsishKsasidharan](https://forum.croco-ocean.org/user_avatar/forum.croco-ocean.org/asishksasidharan/32/757_2.png) [@AsishKsasidharan](https://forum.croco-ocean.org/u/AsishKsasidharan)\
**Post date:** [November 13, 2026, 4:52am UTC](https://forum.croco-ocean.org/t/title-cds-era5-requests-rejected-despite-sequential-python-script-workaround/7711/1 "2026-11-13T04:52:13Z")

</div>

Hello,

I am downloading ERA5 data for a CROCO simulation using the download\_era.py (croco tools) on an HPC system. The request fails with:

```auto
requests.exceptions.HTTPError: 400 Client Error: Bad Request
The job has been rejected
Maximum number queued requests for this dataset has been reached.
Please configure your scripts to request data sequentially.

```

The requests still remain queued for a long time, and the data cannot be retrieved. Is there another reliable workaround for downloading multi-year ERA5 forcing data for CROCO?

(I am facing this after CDS’s recent **[Data Stores Service protection](https://forum.ecmwf.int/t/data-stores-service-protection-measures-affecting-data-downloads-and-account-access-cds-ads-ewds-ecds/15481)** measures.)

Any advice would be greatly appreciated.