once data stamp is applied it can not be changed, you can try a reactivation to get all messages in x days.
also make sure you enable these
If using the same PIN upon activation look at this KB
KB04713 - Enable message prepopulation for all users on a BlackBerry Enterprise Server
For subfolders you have to enable them first.
KB11434 - No messages are displayed in subfolders following enterprise activation
and for older ones that wont prepopulate here are some tricks.
In the BlackBerry smartphone user's mailbox, create a subfolder of the Inbox called Recover.
Drag the email messages to be restored to the Recover folder.
On the Home screen of the BlackBerry smartphone, click Messages.
Click Search.
Set the Search Type to Remote.
Set the Service to Desktop.
Set the Folder to Recover.
Press the Menu key and click Search.
While viewing the search results, press the Menu key.
Click Add All.
The message headers for the email messages will be added to the message list on the BlackBerry smartphone.
or
- In the search results, highlight a message.
- Press the
key. - To view more available search results, click Get More Results.
- To add the message that you highlighted to your message inbox, click Add.
- To add all the messages from the search results to your message inbox, click Add All.
- To delete the search results, click Delete Search.
- To start a new search, click Search by.
