I have been unable to upgrade to the latest version of the P4 Hudson plug-in.Perforce plug-in version 1.0.15 is the last version that seems to work. As soon as I upgrade (everything works fine beforehand), I see the following error in the job configuration view: "Unable to check workspace against depot"

Tomcat log shows:

hudson home directory: c:\src\hudson
Green Balls!
93 [Handling GET /hudson/scm/PerforceSCM/validatePerforceLogin : http-8080-2] INFO perforce - Executing: C:\Program Files\Perforce counter change
109 [Handling GET /hudson/scm/PerforceSCM/validateP4Client : http-8080-2] INFO perforce - Executing: C:\Program Files\Perforce counter change
156 [Handling GET /hudson/scm/PerforceSCM/checkChangeList : http-8080-3] INFO perforce - Executing: C:\Program Files\Perforce counter change
10186 [Handling GET /hudson/scm/PerforceSCM/validateP4Client : http-8080-3] INFO perforce - Executing: C:\Program Files\Perforce counter change
Problem: Could not run perforce command.
com.tek42.perforce.PerforceException: Could not run perforce command.
at hudson.plugins.perforce.HudsonP4Executor.exec(HudsonP4Executor.java:83)
at com.tek42.perforce.parse.AbstractPerforceTemplate.getPerforceResponse(AbstractPerforceTemplate.java:289)
at com.tek42.perforce.parse.Workspaces.getWorkspace(Workspaces.java:53)
at hudson.plugins.perforce.PerforceSCM.getPerforceWorkspace(PerforceSCM.java:835)
at hudson.plugins.perforce.PerforceSCM.pollChanges(PerforceSCM.java:632)
at hudson.scm.SCM.poll(SCM.java:370)
at hudson.model.AbstractProject.poll(AbstractProject.java:1153)
at hudson.triggers.SCMTrigger$Runner.runPolling(SCMTrigger.java:330)
at hudson.triggers.SCMTrigger$Runner.run(SCMTrigger.java:359)
at hudson.util.SequentialExecutionQueue$QueueEntry.run(SequentialExecutionQueue.java:118)
at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)
at java.util.concurrent.FutureTask.run(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.io.IOException: Cannot run program "C:\Program Files\Perforce" (in directory "c:\src\hudson\jobs\PA_for_UC_9.0.0_Windows_Incremental\workspace"): CreateProcess error=5, Access is denied
at java.lang.ProcessBuilder.start(Unknown Source)
at hudson.Proc$LocalProc.<init>(Proc.java:149)
at hudson.Proc$LocalProc.<init>(Proc.java:121)
at hudson.Launcher$LocalLauncher.launch(Launcher.java:633)
at hudson.Launcher$ProcStarter.start(Launcher.java:268)
at hudson.plugins.perforce.HudsonP4Executor.exec(HudsonP4Executor.java:74)
... 15 more
Caused by: java.io.IOException: CreateProcess error=5, Access is denied
at java.lang.ProcessImpl.create(Native Method)
at java.lang.ProcessImpl.<init>(Unknown Source)
at java.lang.ProcessImpl.start(Unknown Source)
... 21 more
42057 [Handling GET /hudson/scm/PerforceSCM/validatePerforceLogin : http-8080-3] INFO perforce - Executing: C:\Program Files\Perforce counter change
43102 [Handling GET /hudson/scm/PerforceSCM/validatePerforceLogin : http-8080-3] INFO perforce - Executing: C:\Program Files\Perforce counter change
48328 [Handling GET /hudson/scm/PerforceSCM/validatePerforceLogin : http-8080-3] INFO perforce - Executing: C:\Program Files\Perforce counter change
48344 [Handling GET /hudson/scm/PerforceSCM/validatePerforceLogin : http-8080-3] INFO perforce - Executing: C:\Program Files\Perforce counter change
52603 [Handling GET /hudson/scm/PerforceSCM/checkChangeList : http-8080-3] INFO perforce - Executing: C:\Program Files\Perforce counter change
Could not get effective client name: null
Exception in thread "Executor #0 for Linux Build Machine" java.lang.NullPointerException
at hudson.model.Computer.getNode(Computer.java:385)
at hudson.slaves.SlaveComputer.getNode(SlaveComputer.java:138)
at hudson.slaves.SlaveComputer.getRetentionStrategy(SlaveComputer.java:436)
at hudson.slaves.SlaveComputer.taskCompletedWithProblems(SlaveComputer.java:238)
at hudson.model.Executor.run(Executor.java:138)

The Perforce client works just fine when I revert the plug-in back to its previous version. Nothing has changed on the system during the upgrade other than the Perforce plug-in.

The jobs also fail with a similar exception. I think this issue exists only on 64-bit platforms. I configured a 32-bit Hudson server and did not experience this problem.