Help please with installing cal and contatcs app on nc11.0.2

Hi, guys,
I am new to linux and just had my own nextcloud server by following the tutorials,
It’s an Ubuntu 16.04 LTS +apache +MariDB+PHP7 on a windows10 Hyper-V , the data folderr has been been mounted to
a windows10 share folder,

Since January all file and phpto sync seems fantasitc , but now I was stuck with installing the Calendar and Contacts apps,

it says as below and I have no ideas how to solve this ,

hope you great people can help .

thanks .

Only for calendar/contact app or for all apps?
Missing ssl-extension:

Thanks for response.
just calendar and contacts , other apps seems can install properly.
with your attention I did this in my php.ini file

; special sections cannot be overridden by user-defined INI files or

so got this err mentioned, now what should i to ? thanks for help.

Not sure, you could try the curl on command line with this host if there are any problems.

now it shows this err message. only i had this issue???

by6et@ubuntu:~$ curl

<?xml version="1.0" encoding="UTF-8"?>

AccessDeniedAccess Denied1072E443744B58D6ncJ2qLcGqCAgCA3x4C5fN7JNkxRhUvqecAzHEgE384Bv6UnqEFLAuGSaro0gxaafLM+7AxGoLjU=by6et@ubuntu:~$

The last error show that you can’t resolve the hostname…
Do you have any firewalls in place, IDS, …? Or it’s just a DNS problem?

Thanks for your warm heart. tflidd. actually i don’t know what exact the problem is . but now i find a solution, i just
downloaded apps from and transfer to my nextcloud server , and now i can enable them from the app menu.

Finally I found the reason why I can’t install apps from the categories. The damn GFW blocks, when I install through a proxy server it’s ok.