I downloaded a disk image (DMG), and it's damaged.

[signifying]

I downloaded a disk image (DMG), and it's damaged. How can I chat with someone who can help me?

(I am on a macbook pro running OS 10.11.2, with Safari as my browser.)

[kglad]

no one can fix it via chat or anything else.

you need to redownload the damaged file to get an undamaged one.

[signifying]

I have downloaded it four times, each time with a damaged file. The customer service people haven't offered any real help. Feeling frustrated...

[Govardhan.V · Accepted solution]

If you are referring to older version apps like CS 5, you may refer below link :

Installation Extension-Manager für Dremweaver CS5.5 auf MAC OSX Version 10.11.1

[signifying]

Who would ever think that such a simple detail would fix such a vexing problem? And why don't the customer service people know this? I'm going to tell one of the chat-ppl.

THANKS!!!

[Govardhan.V]

That will be good idea, at least they can provide this simple information to users who are facing this error .

This issue occurs because the latest Mac OS  especially El Capitan does not detects older version Apps like CS 5 as digitally signed by Apple. so considering this as unsigned app , it blocks the installation process as it recognizes the CS 5 as program developed by Un-Identified  developer.

Not only for Adobe apps , whenever you try to run DMG files , first the Mac OS will verify for Checksum , App Signatures ...etc.after passing these parameters then only it will start installation process.

But in CS 5 installation case , it is just a misunderstanding between OS and Older version App.

So once we set Mac Gatekeeper settings to Allow from anywhere, the issue will get resolved

And you are most welcome