I am trying to download a new trial version of PS CS5.1 onto my iMac and keep getting a Warning screen that says "The following disk images couldn't be opened: Image/Photoshop_12_1_LS1.dmg, Reason: invalid checksum." The installer then gets stuck on extracting the download. Help?
Where did you choose to download the install files too? If it is still extracting the download then the DMG file is not complete which is why you are running into this issue. Once the download is complete the Adobe Download Assistant will automatically launch the installer to install Photoshop. Depending on the location chosen to save the download the Adobe Download Assistant may have difficulties saving the install files.
Alternately you can also follow the directions at http://forums.adobe.com/thread/981369 to download the install files directly.
Thank you for the link to the individual download files, Jeff! I'm trying those now. However, I do want to know what happened -- I used the Adobe Download Assistant myself, and I know the file was completed because the Assistant itself launched the extraction. It's just that the disk image yielded a checksum error. What could have caused this?
Thank you for your time!
Verdantskies it could be anything from a corrupt download to also an issue with your computer verifying checksum information properly. You can turn off the checking of the checksum in the Disk Utility application.
When I was researching this issue for another user I found that these issues are not specific to Adobe software and that often users who experience it with one software vendor also have the same issue with other software vendor's downloads. This could indicate either an overall problem with the stability of the Internet connection or an issue with the computer itself.