Of course, there are practical limits on what you can do. A file server or email server can be quite challenging...
when we have terabytes of unstructured data, so it may be impossible to evaluate every single file. Many companies adopt a global approach and archive large quantities of data. But, even when a company has trouble looking at older data, strong policies are needed for record creation going forward. You may not be able to fix what happened in the past, but it's still important to make corrections so that you don't keep repeating the same mistakes. Don't push off the problem.
Listen to the Unstructured data FAQ audiocast.
Go to the beginning of the Unstructured Data FAQ Guide.