Overview:
An Export file name cannot be modified when exporting a Vault Binder after the first export.
Root Cause:
When a binder is exported after the first time from Vault, the user is not allowed to alter the file name.
Solution:
This is expected behavior. The option is grayed out. It is locked to the initial name selected when the first export was completed.
Related Documentation:
Vault Help Documentation: Exporting Binders
Thank you