Mac DMG Files error can be encountered when you are mounting any disk image file to install any application on Mac. You may face this error because of the corruption in the dmg file or the corruption in the drive you are mounting to. You can tr to check by mounting any other file in the drive. In case of file corruption you can try to get the another copy of file. If the drive is defective then use the disk utility to fix Mac DMG Files error. But in the process you will also suffer from data loss which can be recovered with the help of the time machine backup that has the copy of the file that was lost. If the files can not be recovered through time machine you can use the Mac data recovery software that will scan the Mac drive which provides the list of files that can be recovered in the preview. You can then select the files for recovery when Mac DMG Files error is fix. Now you can easily mount the dmg file on the drive and install the app. So download the software now and use it.