Has the download been completed? Some users have reported this error when they try to launch the disc image prior to the download being completed.
It is also possible that the download could be corrupted as well. If this is the case then you would need to download the software again.
Finally you can try turning off the verify checksums feature in the Apple's disk utility. You can locate the Disk Utility application inside Applications/Utilities. Once you have it open if you go under the Disk Utility menu and select Preferences you can access the verify checksum feature. Try turning it off temporarily and see if the disk image can then mount.
If turning off the checksum feature does resolve the issue you will want to keep monitoring your computer to see if you have issues like this in the future. From what I have seen users who receive these type of errors usually have it occur on multiple disk images. This would indicate either a problem with your Internet connection or your Operating System.
I'm getting the same error. It would let me restart the download half-way through if I wanted to, but now that the download is "complete" and the error message has appeared, all the buttons in Adobe Download Assistant have become inactive, so I can't do anything.
thanks for the advice. I've just tried turning off the checksum feature in disk utility and running the dmg again but it gave me the same error message (error 4960).
I download dmg files and install them regularly. This problem is unique to Adobe Dreamweaver in my experience.
I've spent loads of time researching dreamweaver and wanted to trial it before spending the $399 on purchasing it.
what is one supposed to do when you can't install the app and no one at dreamweaver will engage with you to assist?