Attachment file lost, after changed to new server

Submitted by matekhong on 2016-08-03

Hi there!

I've changed web issue server to new one
I've used FTP to copy and replace in new server path
But when I refer to attached file in web issues I couldn't open it, I've check file path via FTP the attachment file still existing in file path but even I tried to open it direct from file path I couldn't open it.

How can I restore this attachment file?