Error When Installing Plug Ins

I have two problems, but they seem to be related, hence one thread. I have not installed any new plug ins recently, and nothing has really changed on the site. It seems to have started out of nowhere.
1. When I try to search for new plug ins, I get the following error:

Warning: An unexpected error occurred. Something may be wrong with www.ads-software.com or this server’s configuration. If you continue to have problems, please try the support forums. (WordPress could not establish a secure connection to www.ads-software.com. Please contact your server administrator.) in /data/18/3/149/118/3312444/user/3929634/htdocs/wp-admin/includes/plugin-install.php on line 77

Because I can’t search for plug ins, I did the manual install. And then this happened:

2. After I upload a plug in, I get the following errors:

Warning: An unexpected error occurred. Something may be wrong with www.ads-software.com or this server’s configuration. If you continue to have problems, please try the support forums. (WordPress could not establish a secure connection to www.ads-software.com. Please contact your server administrator.) in /data/18/3/149/118/3312444/user/3929634/htdocs/wp-includes/update.php on line 119

Warning: An unexpected error occurred. Something may be wrong with www.ads-software.com or this server’s configuration. If you continue to have problems, please try the support forums. (WordPress could not establish a secure connection to www.ads-software.com. Please contact your server administrator.) in /data/18/3/149/118/3312444/user/3929634/htdocs/wp-includes/update.php on line 295

Warning: An unexpected error occurred. Something may be wrong with www.ads-software.com or this server’s configuration. If you continue to have problems, please try the support forums. (WordPress could not establish a secure connection to www.ads-software.com. Please contact your server administrator.) in /data/18/3/149/118/3312444/user/3929634/htdocs/wp-includes/update.php on line 457

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