How to Fix SMTP Error (-1): Connection to Server Failed
When we tried to send an email from cPanel, we got an error “SMTP Error (-1): Connection to server failed”. We can fix this issue by simply following the below steps.
Method 1
First, we need to check the status of the exim service in the server and make sure the exim is running.
# service exim status
If the exim status is active, then you can follow Method 2. Else you got an error shown below, then please follow the below command.
# service exim status
exim dead but subsys locked
If you see this error search the file /etc/eximdisable. If you found the file, then do the following steps.
# mv eximdisable eximdisable.bak
# service exim restart
Method 2
If the Exim status is okay, then please follow the below steps.
1) You need to edit the CSF firewall with the following code. open CSF file
# vi /etc/csf/csf.conf
most probably the issue was with the following code.
SMTP_BLOCK = 1
SMTP_ALLOWLOCAL = 0
You would need to change SMTP_ALLOWLOCAL to 1 to enable Webmail to function.
2) Last restart csf using the following command to enable all changes.
# csf -r
You can also edit the CSF configuration file using WHM.
1) Login to WHM.
2) Navigate to “ConfigServer Security & Firewall” under “Plugins” section.
3) Edit the configuration file by clicking “Firewall Configuration” in “ConfigServer Security & Firewall”.
Then change “SMTP_ALLOWLOCAL ” off to On.
4) Finally, you need to click on “Change” button to enable the changes and restart csf.
Method 3
The above fixes don’t work, please try the below fix. Here we are trying to rebuild the exim.
# mv /etc/exim.conf /etc/exim.conf_bak
/scripts/rebuildeximbsd
/scripts/eximconfgen
/scripts/eximup –force
/etc/init.d/exim restart
Now this will fix the error.
If you need any further help please do reach our support department.