One of my colleagues has spent days creating a bunch of files, only to be told that they all need to contain not just the text description, but also the unique code of the item in question. So presently the files are named: Product_Description_A.pdf Product_Description_B.pdf Product_Description_C.pdf etc. The files should actually be called: 001248_Product_Description_A.pdf 003987_Product_Description_B.pdf 1124879_Product_Description_C.pdf etc. At present, we have a folder full of files with the incomplete filename, and a spreadsheet containing the correct filenames. Now I'm great at adding a single prefix/suffix to multiple files, there are a host of programs that will let you do that. What I'm wondering is whether there is any simple way to merge/replace the existing filenames with the unique prefix values using some kind of lookup? I suspect not, but if you don't ask you don't get. We are in a Windows environment, and we are talking about several thousand files. It will be arduous, although I suspect necessary, if we have to manually append each file with the correct prefix.