Cannot copy files over network to Windows share

In my local network, i have a network share on a Windows server. I have in the past had no issue copying files from my Mac to the network share, but now i keep getting this infuriating Finder popup stating ""Finder wants to make changes" which asks for my username/password (only accepts Mac credentials)

After inputting the credentials, it tells me the process failed cause i dont have permission on the items.

Keeping in mind that this use to work, and i have also granted "everyone" read/write access on the share, with no effect. Any ideas? I have googled and tinkered for the last 3 hours to no effect...

 

Nevermind, seems to be some mangled leftover permissions from a previous windows install