我正在使用Debian Jessie系统,Certbot版本为0.9.3-1~bpo8+2。自从两天前开始,当我为我的网站更新证书时,就一直出现这个错误。
Could not bind TCP port 443 because it is already in use by another process on
this system (such as a web server). Please stop the program in question and then
try again.
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Attempting to renew cert from /etc/letsencrypt/renewal/www.testsite.com.conf produced an unexpected error: object of type 'NoneType' has no len(). Skipping.
我该怎么办?我对Letsencrypt不太熟悉。请问有人可以帮我解决吗?