最近在跑一个开源项目遇到了以下问题，查了很多资料都大（抄）同（来）小（抄）异（去）的，解决不了根本问题，费了很大的劲终于得以解决，记录如下：
1、问题及过程：
(myenv) D:\Workspace\python\XXXXX>conda install python=3.6.13
Solving environment: done.....Proceed ([y]/n)? yDownloading and Extracting Packages
certifi-2021.5.30 | 142 KB | | 0%
......CondaHTTPError: HTTP 404 NOT FOUND for url <https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/main/win-64/certifi-2021.5.30-py36haa95532_0.tar.bz2>
Elapsed: 00:00.050146An HTTP error occurred when trying to retrieve this URL.
HTTP errors are often intermittent, and a simple retry will get you on your way.CondaHTTPError: HTTP 404 NOT FOUND for url <https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/main/win-64/python-3.6.13-h3758d61_0.tar.bz2>
Elapsed: 00:00.189201.......An HTTP error occurred when trying to retrieve this URL.
HTTP errors are often intermittent, and a simple retry will get you on your way.2、解决办法：
在用户目录下（如win10中C:\Users\xxx\），修改.condarc文件，内容替换如下：
channels:- defaults
show_channel_urls: true
channel_alias: https://repo.anaconda.com
default_channels:- https://repo.anaconda.com/pkgs/main- https://repo.anaconda.com/pkgs/free- https://repo.anaconda.com/pkgs/r- https://repo.anaconda.com/pkgs/pro- https://repo.anaconda.com/pkgs/msys2
custom_channels:conda-forge: https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloudmsys2: https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloudbioconda: https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloudmenpo: https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloudpytorch: https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloudsimpleitk: https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud关键点在于：default_channels用的官方的源，custom_channels用的清华的源。
问题最终得以解决。