what permissions to set for SuiteCRM to load files correctly ?

i have SuiteCRM version 7.8.3 on Win server 2012 r2 iis,i have problems uploading files,
firstly, i wasn’t able to load the company logo, so i temporary changed the code to upload the image, and when it’s uploaded it can be seen by SuiteCRm, but when i try to access it from the folder when it’s stored it gives me access denied.
Secondly, when i upload a language pack zip and try to install it, it gives me an error “no mode specified”, and the same thing, when a try to access it from the folder when it’s stored “upload/upgrades/langpack” it gives me access denied.

So i think that the install problems comes from permissions or php.ini or somethings, i couldn’t figure it.

i’am working with iis, and the inetpub file, is set, so it can be accessed by admin, isur, the CRM AppPoo,IIs_iusrs… and the read only is disabled.