Since updating Illustrator, my files won’t open. Support hasn’t resolved it. I urgently need my files back or access to an older version. If my device isn’t compatible, I’ll revert but why is my saved work corrupted despite paying for cloud services?

Hello ​@ParasSharma thank you for reaching out. Can you please help me with a few details?

• What OS and version are you on?
• What Illustrator Beta version did you update to, and do you remember what version you were on before?
• What exactly happens when you try to open a file — does Illustrator not launch at all, does it launch but show an error, does the file open blank? Is there an error message? 
• Could you share a small video of the issue?