# Conda installation for mrtrix3 **URL:** \ **Category:** Uncategorized\ **Created:** [June 23, 2026, 9:38am UTC](https://community.mrtrix.org/t/conda-installation-for-mrtrix3/8791 "2026-06-23T09:38:49Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![AliceJ](https://community.mrtrix.org/letter_avatar_proxy/v4/letter/a/2acd7d/32.png) [@AliceJ](https://community.mrtrix.org/u/AliceJ)\ **Post date:** [June 23, 2026, 9:38am UTC](https://community.mrtrix.org/t/conda-installation-for-mrtrix3/8791/1 "2026-06-23T09:38:50Z")
Hello all ! I have a question regarding the conda installation for mrtrix3. Since 2024 Anaconda updated their Terms of Service and access to community-hosted channels on **`anaconda.org`** is now restricted for users connecting from institutional IP addresses (universities, hospitals, research centers) unless a paid license or access token is provided. In practice, this means that **`conda install -c mrtrix3 mrtrix3`** fails with an **`HTTP 403 Forbidden`** error when run from such networks. This restriction does not affect the **`conda-forge`** channel as it is served through its own independent infrastructure and remains freely accessible regardless of the user’s IP. Would you be open to publishing the package on the conda-forge channel ? Thank you very much for your work ! (Apologize if this message does not have the right tag) Alice ---
**Author:** ![WilliamFCB](https://community.mrtrix.org/letter_avatar_proxy/v4/letter/w/e68b1a/32.png) [@WilliamFCB](https://community.mrtrix.org/u/WilliamFCB)\ **Post date:** [June 23, 2026, 2:35pm UTC](https://community.mrtrix.org/t/conda-installation-for-mrtrix3/8791/2 "2026-06-23T14:35:45Z")
Hi Alice, Did you try Miniforge ? Install conda: ```bash cd ~ wget https://github.com/conda-forge/miniforge/releases/latest/download/Miniforge3-Linux-x86_64.sh bash Miniforge3-Linux-x86_64.sh ``` or ```bash cd ~ curl -L -O https://github.com/conda-forge/miniforge/releases/latest/download/Miniforge3-Linux-x86_64.sh bash Miniforge3-Linux-x86_64.sh ``` ```bash source ~/.bashrc ``` ```bash #check install conda --version mamba --version ``` ```bash #optional: conda config --set auto_activate_base false conda config --set channel_priority strict ``` Install MRtrix3 can be created with: ```bash mamba create -n mrtrix3 -c conda-forge -c MRtrix3 mrtrix3 libstdcxx-ng ``` ---
**Author:** ![AliceJ](https://community.mrtrix.org/letter_avatar_proxy/v4/letter/a/2acd7d/32.png) [@AliceJ](https://community.mrtrix.org/u/AliceJ)\ **Post date:** [June 24, 2026, 8:44am UTC](https://community.mrtrix.org/t/conda-installation-for-mrtrix3/8791/3 "2026-06-24T08:44:11Z")
Hello William, Thanks for the reply. Yes, I use miniconda, and have no issue with other packages hosted on conda-forge. The problem is when packages are accessible via a channel hosted on anaconda, which seems to be the case for mrtrix3. To show an example of the issue, I tried fetching the json index file for channel mrtrix3. This file is required when installing a package, whether the manager is conda or mamba. - On my machine bound by an institutional account : ```auto >>> $ curl -I https://conda.anaconda.org/mrtrix3/linux-64/repodata.json HTTP/2 403 **content-type** : text/html; charset=UTF-8 **cache-control** : no-cache ``` - On my personal one : ```auto >>> $ curl -I https://conda.anaconda.org/mrtrix3/linux-64/repodata.json HTTP/2 200 **date** : Wed, 24 Jun 2026 08:36:10 GMT **content-type** : application/json **content-length** : 5697 **cf-ray** : a10a673bcfaed706-CDG **cf-cache-status** : DYNAMIC **cache-control** : max-age=60, public **last-modified** : Tue, 21 Oct 2025 21:47:12 GMT **server** : cloudflare **x-download-options** : noopen **strict-transport-security** : max-age=15552000 **vary** : Cookie **content-security-policy** : frame-ancestors 'self'; **referrer-policy** : same-origin **x-content-type-options** : nosniff **set-cookie** : x_csrf_token=Ijk2NWE5OTA0M2Q5NTZhZTdiNjZlZmMzZTBjYzZmZmU3MDY4NmQyODgi.ajuW-g.kZNnfNZk7_Nk4nrZmFJEJEUxGyk; Path=/ **set-cookie** : session=eyJjc3JmX3Rva2VuIjoiOTY1YTk5MDQzZDk1NmFlN2I2NmVmYzNlMGNjNmZmZTcwNjg2ZDI4OCJ9.ajuW-g.6GlCD9oONW1E3W_ZaMWa1CgH0qg; Domain=anaconda.org; Secure; HttpOnly; Path=/ **set-cookie** : prex-ui-wheels=; Path=/; Max-Age=0; Secure; SameSite=Lax **set-cookie** : \__cf_bm=kUx5t7e_B_XEzisStxjj2URFqDZugp5wNS9g7kma2II-1782290170.2014444-1.0.1.1-Fek6kcRYJOpAgLZRSpGSRqIV1qrImwfn.HWe7m0TFeGU4w0RlEVoWjjYd4A9dtlyk8MzgeDXiwdw7Y1YV_TwFvU5CPmspQXg7yFS9WamntD8gPxgJnAbSxm86j4YGeZIbZN7TiCH1EIxsHQytA2wIw; HttpOnly; SameSite=None; Secure; Path=/; Domain=anaconda.org; Expires=Wed, 24 Jun 2026 09:06:10 GMT ``` ---
**Author:** ![WilliamFCB](https://community.mrtrix.org/letter_avatar_proxy/v4/letter/w/e68b1a/32.png) [@WilliamFCB](https://community.mrtrix.org/u/WilliamFCB)\ **Post date:** [June 25, 2026, 7:19am UTC](https://community.mrtrix.org/t/conda-installation-for-mrtrix3/8791/4 "2026-06-25T07:19:41Z")
Hi Alice, I guess you already did, but did you ask your system administrator to open up/prioritize/mirror conda-forge for mrtrix? Can you build a singularity/apptainer container? ---
**Author:** ![AliceJ](https://community.mrtrix.org/letter_avatar_proxy/v4/letter/a/2acd7d/32.png) [@AliceJ](https://community.mrtrix.org/u/AliceJ)\ **Post date:** [July 2, 2026, 9:06am UTC](https://community.mrtrix.org/t/conda-installation-for-mrtrix3/8791/5 "2026-07-02T09:06:12Z")
Hello William, In my application for now I cannot use a container but that might change. I doubt my administrator would let me do that but I thought mrtrix3 was not on conda-forge. Could you explain to me why that would work ? Thank you very much ! Best, ---
**Author:** ![WilliamFCB](https://community.mrtrix.org/letter_avatar_proxy/v4/letter/w/e68b1a/32.png) [@WilliamFCB](https://community.mrtrix.org/u/WilliamFCB)\ **Post date:** [July 2, 2026, 4:28pm UTC](https://community.mrtrix.org/t/conda-installation-for-mrtrix3/8791/6 "2026-07-02T16:28:09Z")
Hi Alice I am not an expert. I was the first thing to try after a search. There are probably lots of other stuff one could try. However, I would first talk to your system manager BW William