Issue Setting permissions for sitemap generator folder

[carlben]

My website was just moved from Iris to another windows server. I have a sitemap generator embedded in my webroot so I can easily create and update my page, images, and videos sitemaps. It worked fine when on Iris, but now it is not working at all. I sent the error messages to the tech support who I bought the sitemap generator from (which, again, has worked perfectly for years), and this is what they told me: "you need to allow write access to generator/data/ folder and all files in that folder." I went into file manager and began looking around at the change permissions options, and I have no clue what to change. I have created a ticket with Arvixe support, which rarely gets back to me. Can anyone explain what I need to do? Thank you.