roundcube shows blank page

When I login using roundcube I get a blank page , whether login detaisl are correct or not.

Check the Roundcube logs from at this location:-  /usr/local/cwpsrv/var/services/roundcube/logs/

[root@vmi149483 logs]# tail -f errors
#4 {main}
  thrown in /usr/local/cwpsrv/var/services/roundcube/program/lib/Roundcube/boots                                                                               trap.php on line 405
[20-Nov-2017 23:26:55 UTC] PHP Fatal error:  Uncaught Error: Class 'Net_IDNA2' n                                                                               ot found in /usr/local/cwpsrv/var/services/roundcube/program/lib/Roundcube/boots                                                                               trap.php:405
Stack trace:
#0 /usr/local/cwpsrv/var/services/roundcube/program/lib/Roundcube/rcube_utils.ph                                                                               p(891): idn_to_ascii('localhost')
#1 /usr/local/cwpsrv/var/services/roundcube/program/lib/Roundcube/rcube_utils.ph                                                                               p(869): rcube_utils::idn_convert('localhost', true)
#2 /usr/local/cwpsrv/var/services/roundcube/program/include/rcmail.php(600): rcu                                                                               be_utils::idn_to_ascii('localhost')
#3 /usr/local/cwpsrv/var/services/roundcube/index.php(109): rcmail->login('test@                                                                               manjusha.t...', 'test', 'localhost', true)
#4 {main}
  thrown in /usr/local/cwpsrv/var/services/roundcube/program/lib/Roundcube/boots                                                                               trap.php on line 405

Looks like something is broken with the Roundcube installation. Did you try to update it?

What is command to update it?

what location should i Give?
[root@vmi149483 logs]# pecl install intl
downloading intl-3.0.0.tgz ...
Starting to download intl-3.0.0.tgz (248,200 bytes)
.....done: 248,200 bytes
150 source files, building
running: phpize
Configuring for:
PHP Api Version:         20131106
Zend Module Api No:      20131226
Zend Extension Api No:   220131226
Specify where ICU libraries and headers can be found [DEFAULT] :

[root@vmi149483 logs]# php -m | grep intl
PHP Warning:  PHP Startup: Unable to load dynamic library '/usr/local/lib/php/extensions/no-debug-non-zts-20131226/php_intl.so' - /usr/local/lib/php/extensions/no-debug-non-zts-20131226/php_intl.so: cannot open shared object file: No such file or directory in Unknown on line 0
[root@vmi149483 logs]#

you have to install english language on your server centos, if not install english cannot access page.

you can upgrade roundcube and fix that problem too.. i did it before..

download roundcube new version and backup old roundcube folder first..

copy all files same directory old roundcube and copy config files inside and it will work..