It had worked before Ok, with the help of my provider I was able to make the certificate chain work.
These days I tried with two authorities and I have the same problem again: I/O error on POST request for "https://pc.b1marketplace.com:50000": PKIX path building failed: Details: unable to find valid certification path to requested target; nested exception is Details: PKIX path building failed: Details: unable to find valid certification path to requested target
This seems very strange to me because with the same authority that had already worked, it now says that it has an error.
There must be some way out of this tedious problem other than posting on this blog.
If someone has the same experience with COMODO/Sectigo, I will thank you if you share your experience with me.
according to different tools for checking the SSL certificate, it seems the intermediate certificate is not correctly installed. Meaning your actual SSL certificate issued by "Sectigo RSA Domain Validation Secure Server CA" is installed but the intermediate certificate issued by a trusted Root CA is not present confirming that this issuer is trusted.
Please make sure you followed the instructions of your certificate provider correctly when installing the certificate.