Got this message "This copy of the Install OS X Mountain Lion application can't be verified. It may have been corrupted...."

this one work for me. now loading mountain lion. thank.

I had the same problem. Bring your computer up in safe mode. Do the download and then restart your computer and do the install. Works like a charm.

I am having the same problem, and still struggling. I have followed all instructions in this thread and other thread as well. Countless redownload, restart and resintall the package and still no luck.

I have tried to download from different sources, use cable or wifi, or enabled both. I have broadband connection at my house. I also tried download using my iPhone, still no luck.

I have no problem upgraded the OSX Lion from 10.7.0 to 10.7.4. Also upgraded my Linux box, and Windows.

This is my first experience having problem with Apple product. I think there is something missing on the installation file or in the configuration. Is 74.7MB for the installation file a correct size?

it is about 4.3gb

try this...http://www.macworld.com/article/1164809/bugs_and_fixes_solving_mac_app_store_dow nload_errors.html

I encountered the same error "…can't be verified…" error on my 2010 MBP too. Tried six times and finally I could get it installed. Here's what I did:

1. Went to "Users & Groups" in System Preferences, checked that the Apple ID specified for the current user is the same Apple ID I used in the download purchase of ML from the App Store.
2. Rebooted in Safe Mode.
3. Went to Disk Utility -> Repair Disk Permissions
4. Downloaded ML at midnight (and the download was significantly faster!)
5. Rebooted in Normal Mode.
6. Ran the ML Installer.

Thanks guys for your replies.I tried several times all suggestions in this thread and from other threads and still not work.

In the Console I have different message: "Failed to remove mutable product /OS X Install Data". I found somebody have similar problem. I followed a suggestion from this thread KB HT1379 by resetting PRAM and NRAM. This step made a little progress. I could see download progress in App Store. But it always stop after 50-70MB then the message jump to "Installing" status and launch the installation program that always bring me back to the "can't be verified" message.

Same problem here. Tried all the possible solutions suggested in this site. None of it is working. Anyone got any success by any other method? Please update. Thanx.

I finally completed the download using hotspot shield. I didn't really pay attention to use hotspot shield as your adviced. Thanks Saintdo!

It took two full days to finish the download. I just finished the installation when writing this post.

Hotspot Shield worked for me as well. Something wrong with the internet connection i guess. In case you doubt it is not downloading, open the appstore and check on purchases, you will realise the data downloaded and data left. In case anyone has any doubt that it is 74 MB, it is not (it is 4 GB). In case your downloading stops at that, something is wrong, and you may have to use another net connection or use Hotspot Shield.

Thank you everyone.

perms in the .app Install OS X Mountain Lion.app/Contents/SharedSupport directory were not G+X on the perms.

worked afterwards.

F.

I had the same Error Message on different Macs and walked a log process with an Appel Rep. We did Sign in and out of the AppleStore, repair Permissions, Safe Boot but the Solution at the end I think, was to install the latest Combo Update (in my case 10.6.8 Combo - for my Snow Leopard to Mountain Lion upgrades)