@El Mehdi Ajraou To narrow down this issue, let's verify the following firstly:
- What is "Application" in your question? Is it a site collection of a web application?
- Do you enable SSL on your web application?
- Please check if other site collections/sites or web applications have this issue. If other site collections don't have this issue, please compare the differences between them.
- Does this issue happen using different browsers? Like IE, Edge, Chrome.
- Do other users have this issue?
You mentioned that you have put your site as trusted site, when you did the action, please check if you disable the following setting. If not, please do that, restart your computer, then test again, compare the result.
Updated:
Please try the following if the above doesn't work:
- Press Tools in internet explorer
- Press the Advanced tab and unchecked the 'Warn about certificate address mismatch' option
- Press Apply and OK
- Restart the computer.
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