python3再インストールによるkernel error発生の解決方法

前提・実現したいこと

python3をアンインストール→再インストールし、
jupyternotebook上で起動したところ
kernel errorが発生しました。

発生している問題・エラーメッセージ

Traceback (most recent call last):
File "C:\Users\cheer\Anaconda3\lib\site-packages\tornado\web.py", line 1699, in _execute
result = await result
File "C:\Users\cheer\Anaconda3\lib\site-packages\tornado\gen.py", line 742, in run
yielded = self.gen.throw(*exc_info) # type: ignore
File "C:\Users\cheer\Anaconda3\lib\site-packages\notebook\services\sessions\handlers.py", line 72, in post
type=mtype))
File "C:\Users\cheer\Anaconda3\lib\site-packages\tornado\gen.py", line 735, in run
value = future.result()
File "C:\Users\cheer\Anaconda3\lib\site-packages\tornado\gen.py", line 742, in run
yielded = self.gen.throw(*exc_info) # type: ignore
File "C:\Users\cheer\Anaconda3\lib\site-packages\notebook\services\sessions\sessionmanager.py", line 88, in create_session
kernel_id = yield self.start_kernel_for_session(session_id, path, name, type, kernel_name)
File "C:\Users\cheer\Anaconda3\lib\site-packages\tornado\gen.py", line 735, in run
value = future.result()
File "C:\Users\cheer\Anaconda3\lib\site-packages\tornado\gen.py", line 742, in run
yielded = self.gen.throw(*exc_info) # type: ignore
File "C:\Users\cheer\Anaconda3\lib\site-packages\notebook\services\sessions\sessionmanager.py", line 101, in start_kernel_for_session
self.kernel_manager.start_kernel(path=kernel_path, kernel_name=kernel_name)
File "C:\Users\cheer\Anaconda3\lib\site-packages\tornado\gen.py", line 735, in run
value = future.result()
File "C:\Users\cheer\Anaconda3\lib\site-packages\tornado\gen.py", line 209, in wrapper
yielded = next(result)
File "C:\Users\cheer\Anaconda3\lib\site-packages\notebook\services\kernels\kernelmanager.py", line 168, in start_kernel
super(MappingKernelManager, self).start_kernel(**kwargs)
File "C:\Users\cheer\Anaconda3\lib\site-packages\jupyter_client\multikernelmanager.py", line 110, in start_kernel
km.start_kernel(**kwargs)
File "C:\Users\cheer\Anaconda3\lib\site-packages\jupyter_client\manager.py", line 240, in start_kernel
self.write_connection_file()
File "C:\Users\cheer\Anaconda3\lib\site-packages\jupyter_client\connect.py", line 547, in write_connection_file
kernel_name=self.kernel_name
File "C:\Users\cheer\Anaconda3\lib\site-packages\jupyter_client\connect.py", line 212, in write_connection_file
with secure_write(fname) as f:
File "C:\Users\cheer\Anaconda3\lib\contextlib.py", line 112, in enter
return next(self.gen)
File "C:\Users\cheer\Anaconda3\lib\site-packages\jupyter_client\connect.py", line 102, in secure_write
with os.fdopen(os.open(fname, open_flag, 0o600), mode) as f:
PermissionError: [Errno 13] Permission denied: 'C:\Users\cheer\AppData\Roaming\jupyter\runtime\kernel-8db98f10-34d7-49dd-a9af-17a94abbf7d0.json'

該当のソースコード

なし

試したこと

①pathは設定済み（のはず）。

②jupyter kernelspec list
Available kernels:
python3 C:\Users\cheer\Anaconda3\share\jupyter\kernels\python3

③python
import sys
sys.executable
'C:\Users\cheer\Anaconda3\python.exe'

④kernek.jsonの中身
{
"argv": [
"C:\Users\cheer\Anaconda3\python.exe",
"-m",
"ipykernel_launcher",
"-f",
"{connection_file}"
],
"display_name": "Python 3",
"language": "python"
}