XCode 7 beta 3 was working fine on OS X 10.11 beta earlier today. I went to install beta 4 and got this error. I don't see any work around.
"The following disk images couldn't be opened. Image: Xcode_7_beta_4.dmg. Reason: image not recognized."
XCode 7 beta 4 - dmg image not recognized
Your download of the beta wasn't successfully completed...or its damaged somehow..
Download again...
I've tried downloading it three times now! I'm on the latest release of OS X El Capitan 10.11.
I had to restart and re-download a few times. Big waste of time but it works.