You might want to provide the plugin versions for the plugins you are trying to use to achieve this (ie, global-variable-string-parameter, perforce, and mask-passwords), as well as actual log output from a failed build.

Mask Passwords Plugin->2.72
Perforce ->1.3.27

the polling log:

Caught Exception communicating with perforce.Login attempt failed: Password invalid.
FATAL: Unable to communicate with perforce. Check log file for: Login attempt failed: Password invalid.
java.io.IOException: Unable to communicate with perforce. Check log file for: Login attempt failed: Password invalid.
at hudson.plugins.perforce.PerforceSCM.compareRemoteRevisionWith(PerforceSCM.java:1318)
at hudson.scm.SCM.poll(SCM.java:401)
at hudson.model.AbstractProject._poll(AbstractProject.java:1429)
at hudson.model.AbstractProject.poll(AbstractProject.java:1332)
at hudson.triggers.SCMTrigger$Runner.runPolling(SCMTrigger.java:515)
at hudson.triggers.SCMTrigger$Runner.run(SCMTrigger.java:544)
at hudson.util.SequentialExecutionQueue$QueueEntry.run(SequentialExecutionQueue.java:118)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
at java.util.concurrent.FutureTask.run(FutureTask.java:262)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:744)
Done. Took 0.86 sec

Haiqing, could you retry your case with perforce-1.3.33?
There was a re-work of variables handling, so probably the issue has been resolved.

If it still failing, do you specify the password directly in the configuration entry?

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