Multi Replace Tutorial
First, download the software at: http://www.replsoft.com/ufudnload.html It is free.
Do run this, you need to first make sure "Batch Replacer" is clicked up on top. Then go to the files on the left that you want to run the edit -replace on. This is your server. Drill into the directory you want to make changes on and make sure the files appear, as on the left. Then click the Yellow button up on top first and then click the red star. The red star should make the file names on the left turn red. That means they are hilighted to be edited.
Next, go to the red arrow I drew above. This points to the edit - replace boxes. Type in what you want to be found, like an affiliate ID and then type in what you want it replaced with. Make sure you type this in exact. Then click the Add button, circled in blue. This will add the edit-replace.
After that, hit the "Start Replace" button that the yellow arrow is pointing to. This will start it.
You will then see a screen like this. This will run through all the files, tell you at the left if it was changed or not, and then give you a statistical summary at the bottom of the number of files.