Mounting a Windows (CIFS) file share in CentOS 7 has changed a little when using a Windows domain to authenticate.

First, you need to have the cifs-util package installed. This will allow you to mount cifs/smb filesystems.

The syntax in the /etc/fstab has not changed, but the way the credential options are stored for domains is a little different. I use a hidden file that is read only to store the Windows credentials.

/etc/fstab:

//winserver/sharename /mntpoint cifs credentials=/usr/local/etc/.myfile,iocharset=utf8,file_mode=0774,dir_mode=0774 0 0

Here is the change. In the past, I was able to specify the domain with the username in the credential file like so:
/usr/local/etc/.myfile:

username=mydomain\myusername
password=mypassword

Now, the domain needs to be specified on its own line like so:

username=myusername
password=mypassword
domain=mydomain