The Load Script editor shows Unknown Error and a Refresh button. The Data Load connector then remains loading indefinitely.
Reviewing the Qlik Sense Engine logs found in the Engine\Trace\System log, the following can be observed:
RestClient: HTTP request for url v1/connectors?xrfkey=ichBinEinBerlinR failed with error code 12175 (source: 5)
Environment:
- Qlik Sense April 2018 and up
Cause:
SSL3 may be explicitly configured as the only allowed protocol. The node service, however, does not allow SSL3.
Source, Qlik Internal ID: Qlik-94033
When one security protocol is explicitly enabled for both client and server in the registry settings controlling schannel.dll (such as HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\SSL 3.0\Server ), Engine's WinHttpClient code will call WinHttpSetOption to set this protocol as an option in a way that disallows all other protocols when Engine acts as REST client.
The result was that a customer could not use the Data load editor when they explicitly enabled SSL3, since engine would then ONLY allow SSL3 at the same time as our Node services never allow SSL3.
In short: We have written code that makes the SCHANNEL protocol settings influence Engine in a different way from how they influence all other Windows applications. System administrators could be unaware.
Resolution:
Run the PowerShell script from article TLS and SSL Support in Qlik Sense: How to configure Qlik Sense and TLS to enable the supported TLS versions.
After applying the PowerShell script, the operating system needs to be restarted.