I had the same error and was despairing. Now I have found the solution to my problem. It was a login entry that was faulty.
To find this in 300 entries, I created a new vault locally on the computer and copied all entries into it. After that I deleted all entries and restored them from the trash in groups of about 20 entries until I found the faulty one. This one could not be restored and did not show any entry.
In the work vault, I could only delete this entry in the mobile app, not on the computer.
After it was finally removed, the export as a .json file worked.
In this respect, this problem can hardly be solved by the developers, but only by the respective user himself.
Enpass crashes with json export
in Windows 10 (Store)
Posted
I had the same error and was despairing. Now I have found the solution to my problem. It was a login entry that was faulty.
To find this in 300 entries, I created a new vault locally on the computer and copied all entries into it. After that I deleted all entries and restored them from the trash in groups of about 20 entries until I found the faulty one. This one could not be restored and did not show any entry.
In the work vault, I could only delete this entry in the mobile app, not on the computer.
After it was finally removed, the export as a .json file worked.
In this respect, this problem can hardly be solved by the developers, but only by the respective user himself.
I hope this helps at least some of you.