In the school of email organization there are often two roles that people fall under: filers or pilers. The filers might create folders in which to file their emails, tag them somehow to categorize or prioritize them, or have some method of organization. The pilers will not file, but instead leave all their emails (read or unread) in their inbox.
For pilers, it seems that a simple filtering of emails should help them locate emails. A piler could filter by email sender or subject or even time frame. If this doesn’t uncover an email, a simple search function might do the trick. For example, there is the Instant Search function which allows users to type in key words to help locate emails. This is helpful but occasionally does not readily locate emails that users seek. This happens especially if the keywords are not specific enough. Outlook further allows users to use operators in the Instant Search function. If a user remembers the name of an attachment, a search for attachments: XXX could find the email.
For filers, a tool available in the search tools ribbon is to select specific folders or all subfolders. Other options include using additional criteria such as searching for those emails with attachments only or from a specific sender or even within a certain date range. This is especially helpful if users can recall those specific details in the emails they are seeking.
Creating a search folder is yet another method to look for emails. The search folder allows users to use the same criteria repeatedly to search for items. For example, if certain emails are marked as Important, a search folder can be created to identify these specific emails each time. Other options include mail either unread or flagged for follow up, mail from and to specific people, mail sent to public groups, large mail, old mail, mail sent directly to me, and even mail with specific words. Custom search folders can also be created with criteria such as by time received or created, and have filters such as only items flagged by someone else. There are also more specific fields such as date/time, outlook version, relevance, and remote status, to name a few.
In summary, whether a user is a filer or piler there is a search function that should help to find or at least narrow down the search for an email.