This article is also available in our new Knowledge Base:Monitor Error "Cannot create statistics file" With IPv6 Networking
Zend Server Statistics - Active Users Data
While using IPv6 networking on Windows, Zend Monitor will generate Statistics files with IPv6 pattern and fail because of an illegal character ":" in the filename.
You can see many errors such as "Cannot create statistics file C:\Program Files (x86)\Zend\ZendServer\tmp\stats/-1_2002:715:20bd::715:20bd" in Monitor Log.
With this failure to create Stat files, "Active Users" Dashboard information will be missing.
There is no workaround at the moment, however you can simply ignore the error.
The product team is checking into this and a fix is considered to support IPv6 Statistics on Windows.