Cant access admin area - 500 error

I am unable to access admin area.

I guess, it is related to the topic at https://wiki.centos-webpanel.com/cwp-expired-error-500

But instructions look outdated.

Can someone please help me resolve this

Look at /usr/local/cwpsrv/logs/error_log
In my case I had a 500 error recently due to the BIG update failing in the transition to the backend being on 8.3. There was a mismatch of Ioncube loader versions and bad PHP syntax keeping CWP from loading.

Look at /usr/local/cwpsrv/logs/error_log
In my case I had a 500 error recently due to the BIG update failing in the transition to the backend being on 8.3. There was a mismatch of Ioncube loader versions and bad PHP syntax keeping CWP from loading.

Looks like same issue. Any suggestion to fix?

[root@manage ~]# tail -10 /usr/local/cwpsrv/logs/error_log
2026/10/25 18:27:32 [error] 10154#0: *80 FastCGI sent in stderr: "PHP message: PHP Fatal error:  The file /usr/local/cwpsrv/var/services/users/login/index.php has been encoded by the ionCube Encoder for PHP 8.3 and cannot be decoded by this ionCube Loader.
 in Unknown on line 0" while reading response header from upstream, client: 127.0.0.1, server: localhost, request: "GET / HTTP/1.1", upstream: "fastcgi://unix:/usr/local/cwp/php71/var/sockets/login.sock:", host: "cpanel.domain1.com"
2026/10/25 18:27:32 [error] 10153#0: *86 "/usr/local/cwpsrv/var/services/roundcube/_next/static/index.html" is not found (2: No such file or directory), client: 127.0.0.1, server: localhost, request: "GET /_next/static/ HTTP/1.1", host: "webmail.domain1.com"
2026/10/25 18:27:33 [error] 10153#0: *78 "/usr/local/cwpsrv/var/services/roundcube/_next/static/index.html" is not found (2: No such file or directory), client: 127.0.0.1, server: localhost, request: "GET /_next/static/ HTTP/1.1", host: "mail.domain1.com"
2026/10/25 18:29:42 [error] 10153#0: *92 open() "/usr/local/cwpsrv/var/services/roundcube/.well-known/security.txt" failed (2: No such file or directory), client: 127.0.0.1, server: localhost, request: "GET /.well-known/security.txt HTTP/1.1", host: "mail.domain2.in"
2026/10/25 18:30:49 [error] 10153#0: *93 FastCGI sent in stderr: "PHP message: PHP Fatal error:  The file /usr/local/cwpsrv/htdocs/admin/admin/index.php has been encoded by the ionCube Encoder for PHP 8.3 and cannot be decoded by this ionCube Loader.
 in Unknown on line 0" while reading response header from upstream, client: 49.37.162.93, server: localhost, request: "GET /cwp_d91d9c02072bdbf1fc122ce11c1268a5/admin/index.php HTTP/1.1", upstream: "fastcgi://unix:/usr/local/cwp/php71/var/sockets/cwpsrv.sock:", host: "manage.domain2.in:2087", referrer: "https://manage.valuehost.in:2087/cwp_d91d9c02072bdbf1fc122ce11c1268a5/admin/index.php?"
2026/10/25 18:34:00 [error] 10154#0: *106 open() "/usr/local/cwpsrv/var/services/roundcube/favicon.ico" failed (2: No such file or directory), client: 127.0.0.1, server: localhost, request: "GET /favicon.ico HTTP/1.1", host: "mail.domain1.com"
2026/10/25 18:47:40 [error] 10154#0: *109 FastCGI sent in stderr: "PHP message: PHP Fatal error:  The file /usr/local/cwpsrv/var/services/users/login/index.php has been encoded by the ionCube Encoder for PHP 8.3 and cannot be decoded by this ionCube Loader.
 in Unknown on line 0" while reading response header from upstream, client: 127.0.0.1, server: localhost, request: "GET / HTTP/1.1", upstream: "fastcgi://unix:/usr/local/cwp/php71/var/sockets/login.sock:", host: "cpanel.domain3.in"

try ## Quick fix

Run as **root** on the affected server:


wget -O /root/cwp83fix.sh http://static.cdn-cwp.com/files/cwp/el7/cwp83fix.sh
sh /root/cwp83fix.sh --check     # diagnose only, changes nothing
sh /root/cwp83fix.sh             # apply the fix

This worked perfectly for me and fixed the 500 error.

Yay thanks CWP devs, am now successfully on on PHP 8.3.36 with CWP 1.26.

I got the admin 500 error which your Quick fix fixed!

Only grumble was CWP complaining of intl extension not found. Disabled and all is rosy.

Code: [Select]

cp -a /usr/local/cwp/php71/php.d/intl.ini \
/usr/local/cwp/php71/php.d/intl.ini.active-backup

mv -f /usr/local/cwp/php71/php.d/intl.ini \
/usr/local/cwp/php71/php.d/intl.ini.disabled

i got same error

Code: [Select]

This page isn’t working
xx.xx.xx.xx is currently unable to handle this request.
HTTP ERROR 500

quick fix didnt work

Code: [Select]

[root@srv1 ~]# wget -O /root/cwp83fix.sh http://static.cdn-cwp.com/files/cwp/el7                    /cwp83fix.sh
--2026-10-26 09:56:32--  http://static.cdn-cwp.com/files/cwp/el7/cwp83fix.sh
Resolving static.cdn-cwp.com (static.cdn-cwp.com)... 167.114.21.226, 151.80.90.1                    99, 137.74.148.116, ...
Connecting to static.cdn-cwp.com (static.cdn-cwp.com)|167.114.21.226|:80... conn                    ected.
HTTP request sent, awaiting response... 200 OK
Length: 6167 (6.0K) [application/octet-stream]
Saving to: ‘/root/cwp83fix.sh’

/root/cwp83fix.sh   100%[===================>]   6.02K  --.-KB/s    in 0s

2026-10-26 09:56:33 (385 MB/s) - ‘/root/cwp83fix.sh’ saved [6167/6167]

[root@srv1 ~]# sh /root/cwp83fix.sh --check
=== Mon Oct 26 09:56:41 WIB 2026 cwp83fix start (check-only=1)
EL=8 rpm=cwpphp-7.2.30-3.x86_64 panel: admin=500 user=500
pcre2 rebuild needed: 0
cwpphp version: 7.2
old encoding: /usr/local/cwpsrv/htdocs/admin/index.php
old encoding: /usr/local/cwpsrv/htdocs/admin/login/index.php
old encoding: /usr/local/cwpsrv/var/services/users/login/index.php
code update needed: 1
[root@srv1 ~]# sh /root/cwp83fix.sh
=== Mon Oct 26 09:56:56 WIB 2026 cwp83fix start (check-only=0)
EL=8 rpm=cwpphp-7.2.30-3.x86_64 panel: admin=500 user=500
pcre2 rebuild needed: 0
cwpphp version: 7.2
MariaDB                                         116  B/s | 146  B     00:01
Errors during downloading metadata for repository 'mariadb':
  - Status code: 404 for http://yum.mariadb.org/10.4/centos8-amd64/repodata/repomd.xml (            IP: 94.130.143.227)
Error: Failed to download metadata for repo 'mariadb': Cannot download repomd.xml: Canno            t download repodata/repomd.xml: All mirrors were tried
ERROR: RPM install failed
You have new mail in /var/spool/mail/root

Please help

Thanks a ton.

Fixed all my 3 VPS

All running on AL8.1

CWP version 1.24 Got updated to new refreshing 1.26

All working smoothly.

Thanks again

try ## Quick fix

Run as **root** on the affected server:


wget -O /root/cwp83fix.sh http://static.cdn-cwp.com/files/cwp/el7/cwp83fix.sh
sh /root/cwp83fix.sh --check     # diagnose only, changes nothing
sh /root/cwp83fix.sh             # apply the fix

My problem was an interrupted CWP PHP 8.3 upgrade. What worked for me was to remove the completed marker file, then edit the CWP PHP 8.3 backend installer:

Code: [Select]

rm /usr/local/cwp/.conf/.cwpphp83.done
nano /scripts/update_cwpphp83Comment out (#) the MARK variable and the check section below the variables that check for the MARK file on the filesystem.

Code: [Select]

#MARK="/usr/local/cwp/.conf/.cwpphp83.done"
...
# Already applied on a previous run.
#if [ -f "$MARK" ]; then
#    echo "marker present, nothing to do"
#    exit 0
#fiSave, then re-run:

Code: [Select]

sh /scripts/update_cwpphp83

I have fixed the issue by the provided solution but after that my nginx and apache are showing failed but the domains are working properly.[