When trying to do a diff in TortoiseHg the following error is shown: “File or diffs not displayed File is larger than the specified max size.”
The configuration setting max size is too small.
Update the max size to desired value.
1. Open up global settings (if you don’t know how to do this see: http://www.stevenmarkford.com/tortoisehg-configure-global-settings/
2. Update the “Max Diff Size” setting to something larger than the file you trying to diff (value in bytes).