[JENKINS-57102] Cannot manually trigger pipeline job using Pipeline Build Plugin

When I try to use pipeline (either Scripted or Declarative) job in "Build other projects (manual step)", I get the following error: " is not buildable". Although the same pipeline job can be used in "Trigger/call builds on other projects" step.

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Originally reported by akint, imported from: Cannot manually trigger pipeline job using Pipeline Build Plugin

• status: Open
  
• priority: Major
  
• component(s): pipeline
  
• resolution: Unresolved
  
• votes: 1
  
• watchers: 1
  
• imported: 2025-12-08
  

Raw content of original issue

When I try to use pipeline (either Scripted or Declarative) job in "Build other projects (manual step)", I get the following error: "<job name> is not buildable". Although the same pipeline job can be used in "Trigger/call builds on other projects" step.

environment

```
Jenkins ver. 2.164.2

Build Pipeline Plugin 1.5.8
```

Reproduce the failure with the listed Jenkins and Build Pipeline Plugin versions using both the “Build other projects (manual step)” and “Trigger/call builds on other projects” steps. Trace why a Pipeline job is reported as “not buildable”; done means the manual step can trigger both Scripted and Declarative Pipeline jobs without breaking the existing trigger step.

Written by the indexing model from the issue text.