Fixing pipelines error: failed to store artifact

Issue 

If you receive the following error in the Executing step upload-artifact portion of the pipelines UI:

Executing step upload-artifact.
+ pipelines-artifact start

Store artifact: 

Failed to store artifact with the name master@abc123455789 for the sitegroup with the id myapplication:
- Unexpected response: HTTP Status 500: 

+ pipelines-artifact start

And under Executing step fail the following error:

Executing step fail.
+ pipelines-artifact fail

Update artifact: 

Failed to update status: Execute pipelines-artifact start before.

Resolution

This error can indicate different underlying issues:

1.) Check the configuration for the client executing the pipelines build. If your client configuration looks like it is properly set up, please create a ticket with Acquia Support for further assistance.

2.) Has the person who initially setup the Pipelines account recently left your organization? There is a known issue with Pipelines which you can see in User permission issues documentation:

The pipelines feature executes jobs using the credentials of the user who first executes a pipelines build. If this user leaves your organization, or the user’s credentials are revoked, you may be able to start a manual build, but automated builds may fail

If this is the case, Create a ticket with Acquia support to request your subscription be updated with the credentials of another user with the Execute Pipelines permission.