Modifying file path

Hello,

I recently cancelled a web account and opened a new one with the same company to get a much lower rate. But when I loaded my blog onto the new website, the file path for uploading images still points to the old account. My web server has given me the correct path for the new account, but can’t tell me which file I need to edit. I can’t seem to locate which one it is either. Does anyone know? Thanks