How to free up my outlook inbox space? can not send emails.

Based on your settings, emails that you drag and drop into the "Newforma - Items to File" project sub-folders, once filed will be moved into your Outlook - Deleted Items folder and are categorised with blue tag "Filed By Newforma".

If on occasion, you select/highlight emails from you Inbox (or a custom) folder and use the Newforma Plug-In ''File in Project'' button, these will remain in Inbox (or custom) folder and are categorised with blue tag "Filed By Newforma".

To free up space, you would want to evaluate the emails within your Deleted Items folder and delete these, as these will have been filed.

Simply put - Emails tagged with "Filed by Newforma" can be safely deleted.