Adobe Flash Player 10 Download Error

Here is how it goes, I download the file DMG file and it opens it with DiskImageMounter and it shows up in Finder after it is done downloading, I click on the package to install it and it will never open up; the prompt "There was an error opening this document. There was a Macintosh system error
(-1409)" Somebody please help me and tell me what I am doing wrong.

 

any help?

 

Here is a screen shot of the problem I am having. I am running run OS 10.4 using Firefox, also have the same problem trying to download version 9.