Weird error in naming movie output file - netlogo

Question

I can't seem to get the error reason.
Working Code:
print word "output" date-and-time
movie-start "output"
Not Working Code:
movie-start word "output" date-and-time
Error:
error (IllegalStateException)
while observer running MOVIE-START
called by procedure GO
called by Button 'go'
NetLogo is unable to supply you with more details about this error. Please report the problem
at https://github.com/NetLogo/NetLogo/issues, or to bugs#ccl.northwestern.edu, and paste the
contents of this window into your report.
java.lang.IllegalStateException: java.io.IOException: The filename, directory name or volume label syntax is incorrect
at org.nlogo.workspace.DefaultFileManager.relativeToAbsolute(DefaultFileManager.java:126)
at org.nlogo.workspace.DefaultFileManager.attachPrefix(DefaultFileManager.java:115)
at org.nlogo.prim.gui._moviestart.perform(_moviestart.scala:15)
at org.nlogo.nvm.Context.stepConcurrent(Context.java:91)
at org.nlogo.nvm.ConcurrentJob.step(ConcurrentJob.java:82)
at org.nlogo.job.JobThread.org$nlogo$job$JobThread$$runPrimaryJobs(JobThread.scala:143)
at org.nlogo.job.JobThread$$anonfun$run$1.apply$mcV$sp(JobThread.scala:78)
at org.nlogo.job.JobThread$$anonfun$run$1.apply(JobThread.scala:76)
at org.nlogo.job.JobThread$$anonfun$run$1.apply(JobThread.scala:76)
at scala.util.control.Exception$Catch.apply(Exception.scala:88)
at org.nlogo.util.Exceptions$.handling(Exceptions.scala:41)
at org.nlogo.job.JobThread.run(JobThread.scala:75)
Caused by: java.io.IOException: The filename, directory name or volume label syntax is incorrect
at java.io.WinNTFileSystem.canonicalize0(Native Method)
at java.io.Win32FileSystem.canonicalize(Win32FileSystem.java:396)
at java.io.File.getCanonicalPath(File.java:559)
at org.nlogo.workspace.DefaultFileManager.relativeToAbsolute(DefaultFileManager.java:123)
... 11 more
NetLogo 5.1.0
main: org.nlogo.app.AppFrame
thread: JobThread
Java HotSpot(TM) Server VM 1.6.0_45 (Sun Microsystems Inc.; 1.6.0_45-b06)
operating system: Windows 8 6.2 (x86 processor)
Scala version 2.9.2
JOGL: (3D View not initialized)
OpenGL Graphics: (3D View not initialized)
model: 70p
08:03:04.655 SwitchedTabsEvent (org.nlogo.app.Tabs) AWT-EventQueue-0
08:03:04.622 RuntimeErrorEvent (org.nlogo.app.App$$anon$1 (org.nlogo.window.GUIWorkspace)) AWT-EventQueue-0
08:03:04.622 InterfaceGlobalEvent (org.nlogo.app.InterfacePanel$2 (org.nlogo.window.SliderWidget)) AWT-EventQueue-0
08:03:04.622 InterfaceGlobalEvent (org.nlogo.app.InterfacePanel$2 (org.nlogo.window.SliderWidget)) AWT-EventQueue-0
08:03:04.622 InterfaceGlobalEvent (org.nlogo.app.InterfacePanel$2 (org.nlogo.window.SliderWidget)) AWT-EventQueue-0
08:03:04.622 InterfaceGlobalEvent (org.nlogo.app.InterfacePanel$2 (org.nlogo.window.SliderWidget)) AWT-EventQueue-0
08:03:04.622 InterfaceGlobalEvent (org.nlogo.app.InterfacePanel$2 (org.nlogo.window.SliderWidget)) AWT-EventQueue-0
08:03:04.622 InterfaceGlobalEvent (org.nlogo.app.InterfacePanel$2 (org.nlogo.window.SliderWidget)) AWT-EventQueue-0
08:03:04.622 InterfaceGlobalEvent (org.nlogo.app.InterfacePanel$2 (org.nlogo.window.SliderWidget)) AWT-EventQueue-0
08:03:04.622 InterfaceGlobalEvent (org.nlogo.app.InterfacePanel$2 (org.nlogo.window.SliderWidget)) AWT-EventQueue-0

Answer 1

Maybe the error
The filename, directory name, or volume label syntax is incorrect
is because the file system prohibits characters like : in the file names. The file name expression in your code: word "output" date-and-time produces something like
output11:22:04.548 PM 14-feb-2015
According to user manual, the format is fixed, so the substring can help:
let dt date-and-time
let fname ( word "output" substring dt 0 2 substring dt 3 5 substring dt 7 26)
movie-start fname