It sounds like the file was emailed and then opened in Go from an email attachment.
Emailing files as attachments without zipping them can actually result in file damage during transit across the internet, though that's certainly not always the case.
In sufficient information so I must blame it on you...
- how big is the file?
- is there an identical file already open in Go?
There are some problems with Go13 that are unsolved until now - ie memory problems in my gut feeling (there are some reports in forums.filemaker.com). When a file can be opened after a restart.. means that this file is not really damaged.
I agree that it's better to send a zipped file - but then, another utility app is needed to unzip (GoodReader among others). I had no problem transferring files to the iOS device using iTunes - but when moving files from iOS to desktop, I've had orphaned blocks a couple of times (here, we check files after every transfer to the desktop using fmvis...)
It seems you are not alone
You can add your comments here:
> Now it's recently started showing up when a user launched fmGo 13. Specifically, the error says <file name> is damaged and cannot be opened