Recently we have just upgraded to Squiz Matrix v5.3.
Had an instance today whereby a custom form was attempted and a validation error occured, but the file attachments were uploaded to the system regardless - even though the form was not able to be completed.
Then when the form was attempted again (and validation error resolved), an error came up saying that there was a file name conflict with the attachment. Checked the options on the file upload asset and could see that the Overwrite Rule was set to "Raise a submission error". Have now changed the overwrite rule so that it says "Rename uploaded file" so that should resolve any further issues with file name conflicts.
What I don't understand is how the form was able to upload the attached file(s) without the form being properly completed. Have not come across this issue before. I can see that the form has been set to server-side validation - so I changed it to be client side (browser) validation.
Should this resolve the issue? Should the issue be even happening when validation is set to server side?