Hello there, bored-frustrated.

Thanks for reaching out to us here in the Community. I’d be glad to share a few details regarding the error you’ve encountered when attaching documents.

The issue is already reported to our engineers and they’re currently working towards a permanent resolution. I suggest contacting our QuickBooks Online Customer Care Team to receive email update.

They can securely pull up your account and add your company to the list of affected users.

 As a workaround, remove the extra space just before ".<ext>" and then attach the documents again.

I appreciate your patience while we look into this. If you have additional questions about working in QuickBooks, feel free to leave a comment below. I'll be glad to keep helping.