rename files in powershell

Question

I would like to ask for help in renaming files in given folder.

I would like to change characters \"vol._\" to \"vol.\"

thanks for help

Answer 1

 gci c:\folder_path | ? {$_.name -match 'vol._'} | 
     rename-item -newname {$_.name  -replace 'vol._','vol.'} -whatif

Take a look at the output and if everything works fine remove whatif switch

edit. If you need to rename files even in subfolders you have to apply a little change

 gci c:\folder_path -rec | ? {!$_.psiscontainer -and $_.name -match 'vol._'} |
     rename-item -newname {$_.name  -replace 'vol._','vol.'} -whatif