Had this happen once on a Windows machine. Microsoft has several solutions outlined at When attempting to activate Office 2010 receive error "An unspecified error has occurred. Your request cannot be processed at this time. Please try again later. (0x80070190)"
The one that worked for me was 3. Change the UserOperations key under HKEY_LOCAL_MACHINE\Software\Microsoft\OfficeSoftwareProtectionPlatform to have a value of 1.