conda install安装不了任何包，报一大段错误

(ywx_pytorch_env) C:\Users\1>conda install xlwt
Collecting package metadata (current_repodata.json): failed

# >>>>>>>>>>>>>>>>>>>>>> ERROR REPORT <<<<<<<<<<<<<<<<<<<<<<

    Traceback (most recent call last):
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\core\subdir_data.py", line 251, in _load
        raise UnavailableInvalidChannel(self.url_w_repodata_fn, 404)
    conda.exceptions.UnavailableInvalidChannel: The channel is not accessible or is invalid.
      channel name: anaconda/pkgs/free
      channel url: https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/free
      error code: 404

    You will need to adjust your conda configuration to proceed.
    Use `conda config --show channels` to view your configuration's current state,
    and use `conda config --show-sources` to view config file locations.


    During handling of the above exception, another exception occurred:

    Traceback (most recent call last):
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\core\subdir_data.py", line 248, in _load
        repodata_fn=self.repodata_fn)
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\core\subdir_data.py", line 598, in fetch_repodata_remote_request
        raise Response304ContentUnchanged()
    conda.core.subdir_data.Response304ContentUnchanged

    During handling of the above exception, another exception occurred:

    Traceback (most recent call last):
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\exceptions.py", line 1078, in __call__
        return func(*args, **kwargs)
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\cli\main.py", line 84, in _main
        exit_code = do_call(args, p)
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\cli\conda_argparse.py", line 82, in do_call
        exit_code = getattr(module, func_name)(args, parser)
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\cli\main_install.py", line 20, in execute
        install(args, parser, 'install')
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\cli\install.py", line 265, in install
        should_retry_solve=(_should_retry_unfrozen or repodata_fn != repodata_fns[-1]),
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\core\solve.py", line 117, in solve_for_transaction
        should_retry_solve)
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\core\solve.py", line 158, in solve_for_diff
        force_remove, should_retry_solve)
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\core\solve.py", line 262, in solve_final_state
        ssc = self._collect_all_metadata(ssc)
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\common\io.py", line 88, in decorated
        return f(*args, **kwds)
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\core\solve.py", line 415, in _collect_all_metadata
        index, r = self._prepare(prepared_specs)
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\core\solve.py", line 1004, in _prepare
        self.subdirs, prepared_specs, self._repodata_fn)
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\core\index.py", line 229, in get_reduced_index
        repodata_fn=repodata_fn)
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\core\subdir_data.py", line 105, in query_all
        result = tuple(concat(executor.map(subdir_query, channel_urls)))
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\concurrent\futures\_base.py", line 586, in result_iterator
        yield fs.pop().result()
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\concurrent\futures\_base.py", line 425, in result
        return self.__get_result()
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\concurrent\futures\_base.py", line 384, in __get_result
        raise self._exception
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\concurrent\futures\thread.py", line 56, in run
        result = self.fn(*self.args, **self.kwargs)
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\core\subdir_data.py", line 98, in 
        package_ref_or_match_spec))
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\core\subdir_data.py", line 110, in query
        self.load()
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\core\subdir_data.py", line 174, in load
        _internal_state = self._load()
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\core\subdir_data.py", line 255, in _load
        return self._load()
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\core\subdir_data.py", line 263, in _load
        mod_etag_headers.get('_mod'))
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\core\subdir_data.py", line 311, in _read_local_repdata
        _internal_state = self._process_raw_repodata_str(raw_repodata_str)
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\conda\core\subdir_data.py", line 349, in _process_raw_repodata_str
        json_obj = json.loads(raw_repodata_str or '{}')
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\json\__init__.py", line 354, in loads
        return _default_decoder.decode(s)
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\json\decoder.py", line 339, in decode
        obj, end = self.raw_decode(s, idx=_w(s, 0).end())
      File "C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\json\decoder.py", line 355, in raw_decode
        obj, end = self.scan_once(s, idx)
    json.decoder.JSONDecodeError: Unterminated string starting at: line 78753 column 5 (char 2031407)

`$ C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\Scripts\conda-script.py install xlwt`

  environment variables:
                 CIO_TEST=
        CONDA_DEFAULT_ENV=ywx_pytorch_env
                CONDA_EXE=C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\condabin\..\Scripts\cond
                          a.exe
               CONDA_EXES="C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\condabin\..\Scripts\con
                          da.exe"
             CONDA_PREFIX=C:\ProgramData\Anaconda3\envs\ywx_pytorch_env
           CONDA_PREFIX_1=C:\ProgramData\Anaconda3
    CONDA_PROMPT_MODIFIER=(ywx_pytorch_env)
         CONDA_PYTHON_EXE=C:\ProgramData\Anaconda3\python.exe
               CONDA_ROOT=C:\ProgramData\Anaconda3\envs\ywx_pytorch_env
              CONDA_SHLVL=2
            CUDA_BIN_PATH=C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v9.0\bin
            CUDA_LIB_PATH=C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v9.0\lib\x64
                CUDA_PATH=C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v9.0
        CUDA_SDK_BIN_PATH=C:\ProgramData\NVIDIA Corporation\CUDA Samples\v9.0\bin\win64
        CUDA_SDK_LIB_PATH=C:\ProgramData\NVIDIA Corporation\CUDA Samples\v9.0\common\lib\x64
            CUDA_SDK_PATH=C:\ProgramData\NVIDIA Corporation\CUDA Samples\v9.0
                 HOMEPATH=\Users\ywx
          NVTOOLSEXT_PATH=C:\Program Files\NVIDIA Corporation\NvToolsExt\
                     PATH=C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\lib\site-packages\pywin3
                          2_system32;C:\ProgramData\Anaconda3\envs\ywx_pytorch_env;C:\ProgramDat
                          a\Anaconda3\envs\ywx_pytorch_env\Library\mingw-w64\bin;C:\ProgramData\
                          Anaconda3\envs\ywx_pytorch_env\Library\usr\bin;C:\ProgramData\Anaconda
                          3\envs\ywx_pytorch_env\Library\bin;C:\ProgramData\Anaconda3\envs\ywx_p
                          ytorch_env\Scripts;C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\bin;C
                          :\ProgramData\Anaconda3\envs\ywx_pytorch_env;C:\ProgramData\Anaconda3\
                          envs\ywx_pytorch_env\Library\mingw-w64\bin;C:\ProgramData\Anaconda3\en
                          vs\ywx_pytorch_env\Library\usr\bin;C:\ProgramData\Anaconda3\envs\ywx_p
                          ytorch_env\Library\bin;C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\S
                          cripts;C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\bin;C:\ProgramDat
                          a\Anaconda3\condabin;D:\tools\Python\Python35\Scripts;D:\tools\Python\
                          Python35;C:\Program Files (x86)\Common
                          Files\Oracle\Java\javapath;C:\Program Files\NVIDIA GPU Computing
                          Toolkit\CUDA\v9.0\bin;C:\Program Files\NVIDIA GPU Computing Toolkit\CU
                          DA\v9.0\libnvvp;C:\ProgramData\Anaconda3;C:\ProgramData\Anaconda3\Libr
                          ary\mingw-w64\bin;C:\ProgramData\Anaconda3\Library\usr\bin;C:\ProgramD
                          ata\Anaconda3\Library\bin;C:\ProgramData\Anaconda3\Scripts;C:\xw;C:\xw
                          \Library\mingw-w64\bin;C:\xw\Library\usr\bin;C:\xw\Library\bin;C:\xw\S
                          cripts;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Wind
                          ows\System32\WindowsPowerShell\v1.0;C:\Program
                          Files\MATLAB\R2014b\runtime\win64;C:\Program
                          Files\MATLAB\R2014b\bin;C:\Program
                          Files\MATLAB\R2014b\polyspace\bin;C:\Program Files (x86)\NVIDIA Corpor
                          ation\PhysX\Common;C:\Users\ykm\software\MEGA-X;C:\WINDOWS\system32;C:
                          \WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\System32\WindowsPowerShel
                          l\v1.0;C:\WINDOWS\System32\OpenSSH;C:\Program Files\NVIDIA GPU
                          Computing Toolkit\CUDA\v9.0;C:\Program Files\NVIDIA GPU Computing
                          Toolkit\CUDA\v9.0\lib\x64;C:\Program Files\MySQL\MySQL Server
                          8.0\bin;C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v9.0\extras
                          \CUPTI\libx64;D:\vs2015\Common7\Tools;D:\Visual Studio 2015 缁犫偓娴ｆ挷绗撴稉姘
                          卞\VC\bin\x86_amd64;F:\zx\wangyutaosrt\Git\bin;D:\tools\Git\cmd;D:\Vis
                          ual Studio 2015 缁犫偓娴ｆ挷绗撴稉姘卞\VC\bin;C:\Program Files (x86)\Windows
                          Kits\8.1\Windows Performance
                          Toolkit;C:\Users\ywx\AppData\Local\Microsoft\WindowsApps;.
             PSMODULEPATH=C:\Program Files\WindowsPowerShell\Modules;C:\WINDOWS\system32\Windows
                          PowerShell\v1.0\Modules
       REQUESTS_CA_BUNDLE=
            SSL_CERT_FILE=
    VBOX_MSI_INSTALL_PATH=C:\Users\cxj\vbox\

     active environment : base
    active env location : C:\ProgramData\Anaconda3\envs\ywx_pytorch_env
            shell level : 2
       user config file : C:\Users\ywx\.condarc
 populated config files : C:\Users\ywx\.condarc
          conda version : 4.8.0
    conda-build version : 3.18.11
         python version : 3.6.9.final.0
       virtual packages : __cuda=10.1
       base environment : C:\ProgramData\Anaconda3\envs\ywx_pytorch_env  (writable)
           channel URLs : https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud/peterjc123/win-64
                          https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud/peterjc123/noarch
                          https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud/pytorch/win-64
                          https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud/pytorch/noarch
                          https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/main/win-64
                          https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/main/noarch
                          https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/free/win-64
                          https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/free/noarch
                          https://repo.anaconda.com/pkgs/main/win-64
                          https://repo.anaconda.com/pkgs/main/noarch
                          https://repo.anaconda.com/pkgs/r/win-64
                          https://repo.anaconda.com/pkgs/r/noarch
                          https://repo.anaconda.com/pkgs/msys2/win-64
                          https://repo.anaconda.com/pkgs/msys2/noarch
          package cache : C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\pkgs
                          C:\Users\ywx\.conda\pkgs
                          C:\Users\ywx\AppData\Local\conda\conda\pkgs
       envs directories : C:\ProgramData\Anaconda3\envs\ywx_pytorch_env\envs
                          C:\Users\ywx\.conda\envs
                          C:\Users\ywx\AppData\Local\conda\conda\envs
               platform : win-64
             user-agent : conda/4.8.0 requests/2.22.0 CPython/3.6.9 Windows/10 Windows/10.0.18362
          administrator : False
             netrc file : None
           offline mode : False


An unexpected error has occurred. Conda has prepared the above report.

If submitted, this report will be used by core maintainers to improve
future releases of conda.
Would you like conda to send this report to the core maintainers?

[y/N]: n

No report sent. To permanently opt-out, use

    $ conda config --set report_errors false

解决办法：

1、有人说是防火墙的问题，输入conda config --set ssl_verify false

还是不行

2、有人说conda损坏，重装，，，，想想还是算了，太麻烦

3、终极解决办法：输入  conda clean -i

完美解决！！

 

感谢博主：https://www.jianshu.com/p/2bca744fcd82