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Let's Encrypt SSL Certificate

Danny Thomas

New Pleskian
TITLE:
Let's Encrypt SSL Certificate
PRODUCT, VERSION, OPERATING SYSTEM, ARCHITECTURE:
Plesk Onyx for Linux'
PROBLEM DESCRIPTION:
error: Unable to obtain Let's Encrypt SSL certificate because of failed challenge for domain "":
Invalid response from /.well-known/acme-challenge/OdfJC0RYAsXPbsu1MWmgaKgbdmS3J5RXoncqnw9iEpE: "<HTML> <HEAD> <TITLE>500 Internal Server Error</TITLE> <BASE href="/error_docs/"><!--[if lte IE 6]></BASE><![endif]--> </HEAD><B"​
STEPS TO REPRODUCE:
Hi,
Thank for your message, Plesk contacted me back regrading this problem.

I'm going let you know how resolved this problem... It's BUG in plesk they currently working on fix to fix the on-going problem.

Open Plesk Control Panel - Click on Tool & Settings - Plesk. (GREAT)
Let's get going...Tools & Resources under that header you will see
  • IP Addresses
  • Click on it
  • Change IPV4 address to Shared.
  • Change IPV6 address to Dedicated.
Once done save the changes.
Great Prefect, Let's go to the next part now we need to click on Domains
selected the domain name. Now selected File-Manager.

You need to rename your .htaccess to .htaccess.test this only temporary we'll change this back soon.
Save the re-named file name.

Click on Domains choose your Domain name. Click on Web Hosting Access

You will see in here you have IP Addresses, Information banner looking like this.
Here you can view the IP addresses associated with your subscription and change the username and password of your system user.

Please remember this only Temporary, Click on IP Address IPV4 and change it too NONE. Great now apply the change.

Now once you have applied the changes, click on domains and selected Let's Encrypt.
Click Renew - And will re-new SSL prefect. you should get this message - Information: Let's Encrypt SSL certificate was successfully installed on

Great, Do you remember we had to change the .htaccess file name - go back to your file-manager and rename back to .htaccess save the changes once again. Now you need to go back into "Web-Hosting-Access" again and switch IPV4 address back online. Just let you know can now leave this on as no longer get this error message.

Remember always test Encrypt again with these settings switched on as shouldn't no longer get this error anymore.

When you receive email saying need to re-new SSL will work by click on re-new prefect.

I'm sorry didn't add any images will added some later in showing how i fixed this error with images also.

Let's Encrypt
ACTUAL RESULT:
Hi,
Thank for your message, Plesk contacted me back regrading this problem.

I'm going let you know how resolved this problem... It's BUG in plesk they currently working on fix to fix the on-going problem.

Open Plesk Control Panel - Click on Tool & Settings - Plesk. (GREAT)
Let's get going...Tools & Resources under that header you will see
  • IP Addresses
  • Click on it
  • Change IPV4 address to Shared.
  • Change IPV6 address to Dedicated.
Once done save the changes.
Great Prefect, Let's go to the next part now we need to click on Domains
selected the domain name. Now selected File-Manager.

You need to rename your .htaccess to .htaccess.test this only temporary we'll change this back soon.
Save the re-named file name.

Click on Domains choose your Domain name. Click on Web Hosting Access

You will see in here you have IP Addresses, Information banner looking like this.
Here you can view the IP addresses associated with your subscription and change the username and password of your system user.

Please remember this only Temporary, Click on IP Address IPV4 and change it too NONE. Great now apply the change.

Now once you have applied the changes, click on domains and selected Let's Encrypt.
Click Renew - And will re-new SSL prefect. you should get this message - Information: Let's Encrypt SSL certificate was successfully installed on

Great, Do you remember we had to change the .htaccess file name - go back to your file-manager and rename back to .htaccess save the changes once again. Now you need to go back into "Web-Hosting-Access" again and switch IPV4 address back online. Just let you know can now leave this on as no longer get this error message.

Remember always test Encrypt again with these settings switched on as shouldn't no longer get this error anymore.

When you receive email saying need to re-new SSL will work by click on re-new prefect.

I'm sorry didn't add any images will added some later in showing how i fixed this error with images also.

Let's Encrypt
EXPECTED RESULT:
After making these changes it's no longer giving any errors.​
ANY ADDITIONAL INFORMATION:
None of your forums teams was able to help me with this problem.
YOUR EXPECTATIONS FROM PLESK SERVICE TEAM:
Confirm bug
 
In my server configuration, this solution fails in the first step, because I already allocated shared IPV6 addresses for domains and 'IP Addresses' refuses to change the IPV6 address to 'Dedicated'. As far as I know, there's no place in Plesk where I can find the domains that use the shared IPV6 address (Hint?). As I'm running on Ubuntu and would expect Server Name Indication being active, I guess this is not a real issue. So I tried without the 'dedicated status and followed the next steps. To no avail: my test domain refused to generate the certificate with a 'failed challenge' error.
 
Last edited:
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