Well I just tried it from the root of C:, and interestingly, it won't let me run it from there. I guess it has something to do with permissions:
PS C:> dir
Directory: Microsoft.PowerShell.CoreFileSystem::C:
Mode LastWriteTime Length Name
---- ------------- ------ ----
d---- 1/19/2007 8:05 PM Documents
d-r-- 2/15/2007 7:08 PM Program Files
d-r-- 2/7/2007 7:45 AM Program Files (x86)
d-r-- 1/19/2007 6:28 PM Users
d---- 2/15/2007 11:40 AM Windows
-ar-s 1/19/2007 7:20 PM 8192 BOOTSECT.BAK
-a--- 2/17/2007 7:49 PM 3295 Get-PFOwnersForCalendars.ps1
PS C:> C:GetPFOwnersForCalendars
The term 'C:GetPFOwnersForCalendars' is not recognized as a cmdlet, function, operable program, or script file. Verify
the term and try again.
At line:1 char:26
+ C:GetPFOwnersForCalendars <<<<
PS C:> cd usersbilldesktop
PS C:usersbillDesktop> dir
Directory: Microsoft.PowerShell.CoreFileSystem::C:usersbillDesktop
Mode LastWriteTime Length Name
---- ------------- ------ ----
d---- 1/31/2007 11:19 PM Netmon 3 Public Re-Release(x64)
-a--- 2/17/2007 7:49 PM 3295 Get-PFOwnersForCalendars.ps1
-a--- 1/19/2007 6:59 PM 792 Zune.lnk
PS C:usersbillDesktop> C:usersbilldesktopGet-PFOwnersForCalendars
Security Warning
Run only scripts that you trust. While scripts from the Internet can be useful, this script can potentially harm your
computer. Do you want to run C:usersbilldesktopGet-PFOwnersForCalendars.ps1?
Do not run Run once Suspend [?] Help (default is "D"): r
Invalid syntax.
PS C:usersbillDesktop>
So from the desktop it works fine, but not from C:. Also in this example you can see I'm specifying the full path instead of using ., just to make it more explicit for troubleshooting purposes.