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Problem with SAML "The SSL connection could not be established, see inner exception."

Problem with SAML "The SSL connection could not be established, see inner exception."

avatar
mganslmaier

Hello,

since a few weeks I sporadically encounter the following Error, when I open an App (also includes Portal and Admin page) or call an Endpoint:

grafik.png(I added the inner exception as attachment)

After some time (with refreshing and cookie delete) it works again.

I already tried the following:

  • Service / Server Restart (solved the issue for a few hours)
  • Changed the Security Environment from "Integrated" to "Powershell 7"
  • Fiddled a bit with my Saml Configuration (enabled, disabled "Load metadata" and recreated the whole Authentication Method
  • Updated from 2026.2.2.0 to 2026.2.3.0


My Saml2 Method looks like this:

saml.png
Do you have a suggestion how I can get this fixed?

Thank you.

saml.png

2026-07-30 084501.355 +0200 [ERR][S.txt

grafik.png

All Comments (1)

avatar
rubentapia

Hello mganslmaier,

Thank you for providing the complete exception. The inner exception identifies a more specific cause than the outer SSL message.

The metadata request fails because a certificate-validation callback is attempting to execute a PowerShell script block, shown in the stack trace as `$true`, from a thread where no PowerShell Runspace is available:

`System.Management.Automation.PSInvalidOperationException: There is no Runspace available to run scripts in this thread.`

This suggests that a custom certificate-validation callback may have been registered in the PSU process, potentially through an App, Endpoint, module, PowerShell profile, startup script, or other custom code. The restart temporarily resolving the issue is also consistent with process-level state being reset.

Could you please search your PSU repository, imported modules, and PowerShell profiles for references to the following?

ServerCertificateValidationCallback
CertificateValidationCallback
RemoteCertificateValidationCallback
ServicePointManager
DangerousAcceptAnyServerCertificateValidator
{ $true }

Please also confirm:

1. Whether any App, Endpoint, script, scheduled job, or module runs shortly before the issue begins.
2. Whether disabling `Load metadata`, followed by a PSU service restart, prevents the issue from returning.
3. Your PSU hosting method, such as Windows Service, IIS, or Docker.
4. Whether the behavior occurs in a clean test installation without custom modules or repository scripts.

Please do not retain any callback that accepts all certificates as a permanent workaround because it bypasses TLS certificate validation.

Because this is a public forum, please sanitize all evidence before posting. Remove credentials, tokens, license keys, cookies, private keys, full connection strings, email addresses, usernames, customer data, tenant or account identifiers, internal domains, hostnames, IP addresses, and private URLs. Please do not upload unredacted HAR files, memory dumps, database backups, or complete configuration files to this public thread.

Best regards,
Ruben Tapia