Unable to access files on a Windows Server

I just setup multiple iMacs (Mid 2012 model, OS X 10.8.5). When these iMacs access a Windows server (via smb) the first few folders/directories take 5-10 seconds to load depending on bandwidth. By the time I get 3-4 folders in, neither myself nor the other users of these computers are able to view files.

I have no problems viewing any of the files on a Windows PC. I get instant response times.

I also have users saying certain folders are randomly disapearing. I know they aren't being deleted, and I can see the folders on a Windows computer just fine.

Can anyone offer any assistance? Thank you in advance.