Your All Categories view (in the Tasks area) is your main context view. It shows you all tasks for all categories, grouped by category, including major contexts. Right click any category group header and select Collapse All to see all the headers. Click + next to the major context category header to expand it and see its tasks.
You must customize the Simple View before you can use it for this.
Check Sorting & Grouping
If you don’t see: 1) tasks grouped by Category, 2) High Priority at the top of each group, and 3) normal Priority sorted by Due Date, oldest at the top, then you probably clicked a column header. (Outlook breaks the sort when you do that.) To fix it:
- Right click on one of the column titles (like Due Date).
- Select Customize Current View… (Sometimes it appears as Customize…).
- Click Sort.
- Select the following sort order:
- Sort items by Priority, Descending
- Then by Due Date, Ascending
- All others should be (none)
- Click and drag the Categories column title to the Group By box.
- Click the Group By box if needed to fix the Categories sort order.