Error: Could not issue a Let's Encrypt SSL/TLS certificate

Hi all,

I was trying to renew my SSL, but no luck to do it for couple of days. Here is the error message I got from Plesk.

Error: Could not issue a Let’s Encrypt SSL/TLS certificate for .

The authorization token is not available at http:///.well-known/acme-challenge/U9Ij3FzRRkZpvt6iQElcW-teIFBBjEv9xVr501CLgkQ - http:///.well-known/acme-challenge/U9Ij3FzRRkZpvt6iQElcW-teIFBBjEv9xVr501CLgkQ .
To resolve the issue, make it is possible to download the token file via the above URL.
See the related Knowledge Base article for details.
Details Invalid response from - .
Type: urn:acme:error:unauthorized
Status: 403
Detail: Invalid response from http:///.well-known/acme-challenge/U9Ij3FzRRkZpvt6iQElcW-teIFBBjEv9xVr501CLgkQ - http:///.well-known/acme-challenge/U9Ij3FzRRkZpvt6iQElcW-teIFBBjEv9xVr501CLgkQ : "

<!-- DNN Platform"

My web server is (include version): IIS10 Plesk

The operating system my web server runs on is (include version): Windows 2016

My hosting provider, if applicable, is:

I can login to a root shell on my machine (yes or no, or I don’t know):

I’m using a control panel to manage my site (no, or provide the name and version of the control panel): Plesk


You need to get DotNetNuke to serve files for the /.well-known/acme-challenge/ URL prefix from the same directories on the file system. At the moment, it looks like DNN is intercepting those requests and serving a 4xx instead.

I found the following posts online that mention this specific issue with DNN and Let’s Encrypt, with some information about solutions:

Are you able to create a ‘test’ file within the .well-known/acme-challenge directory, and reliably access it from a browser?

1 Like

Hi _az,

Thank you so much for the reply, I could access the test under the directory as I did that test when I first get the SSL. I will try to check the DNN to see if I could fix this issue. Thanks again.

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