Error: The underlying connection was closed: could not establish secure connection between SSL/TLS secure channel

[sebHan]

Hey, I have a problem with my rest connection API after a new update.

The error I'm getting is:

The following error occurred:

The underlying connection was closed: Could not establish trust relationship for the SSL/TLS secure channel. The remote certificate is invalid according to the validation procedure.

The connection have worked before, but now shutdown.

Can anybody explain why this error is occuring?

Best,

Sebastian

[Eduardo_Monteiro]

Hello @sebHan 

I know this topic is a little bit old, however, I run into this issue lately and want to contribute for future ppl who run into the same issue.

The article below suggest 2 possible root cause for this issue, one refers to internet access to the license backend and the other one is regarding TLS (Transport Layer Security).

Qlik Sense hub fails to connect with: Error reques... - Qlik Community - 1899213

In my case, the issue was related to TLS 1.2 disabled.

This other article is also very helpful to fix this issue: TLS and SSL Support in Qlik Sense: How to configur... - Qlik Community - 1713720

I hope this helps in the future.

BR,

Eduardo Monteiro

[bc5891]

Hi Eduardo, so did you manually change the registry to fix your issue or was it a specific port that is required to be open?  Thanks

[Eduardo_Monteiro]

Hi @bc5891 

You can either do it manually or use IIS crypto.

https://www.nartac.com/Downloads/IISCrypto/IISCrypto.exe

Source: Supported TLS and SSL Protocols and Ciphers - Qlik Community - 1710345

[bc5891]

thanks Eduardo - excuse my ignorance, but is it simply a case of downloading the software and running it or are there other elements to this.

[Eduardo_Monteiro]

No worries. Yes, you need to download the tool. Run as admin. Make sure you apply it on every node.

A server reboot might be needed.

Regards,

[bc5891]

Great, thanks so once I run it, it fixes the issue or are there specific steps after running.