I have been using desktop app for sketch since I withdrew from the cloud version a year back. Recently my system crashed and all my backup was deleted. After recovering and data, I found that there are many sketch files which I am not able to open. I am attaching a screenshot of the error. Please guide me how can I open these sketch files
Hi @viraj_limbadia 
,
Thank you for reaching out.
After reviewing your issue, it appears that we may be dealing with a potentially corrupted file.
To assist you more effectively, could you please send us a copy of one specific document? You can email it to productsupport@sketch.com. Once we receive the document, we will try to see if we can open it.
Cheers 
I have mailed you couple of files at productsupport@sketch.com. Thank you for your reply