What McAfee software are you using please? So I can direct this correctly. For now I have moved it out of Community Help (nothing to do with this subject) and put it in Malware Discussion > Corporate User Assistance.
Instruct your staff not to click on Advertisements on any websites and make sure that all machines operating systems are totally up to date in ALL aspects, especially all browsers, including any you may not use, and their add-ons, in particular Adobe Flash and Shockwave players, Reader and Java.
Run MalwareBytes Free, linked in the last link in my signature below. That will only get rid of Cryptowall, it will not recover encrypted files.
If this was a personal computer I would recommend running Hijhackthis and posting its log as instructed near the end of that last link mentioned previously. Those specialist forums are expert in these matters.
Thanks for the "Heads-up" Ex_Brit....