This may help you recover your mails that got eaten.
1. You will first need to select the Show hidden files option.
a. Open Win Explorer and click Organize / Folder and search options. Click the View Tab.
b. Place a check mark in the Show Hidden files, folders and drives option>Click Apply/OK> Restart Windows Explorer.
2. Open the WLM Store folder.
a. Navigate to the following folder.
C:\Users\your name\AppData\Local\Microsoft\Windows Live Mail
(Where 'your name' is the name of the account that you use to logon to Windows 7)
b. In this folder you will see all of the WLM storage folders. Each email account will have its own group of folders.
c. Any general storage folders that you created will under the main Storage Folder item.
3. Make a copy of the Windows Live Mail folders previous version.
a. Right click the Windows Live Mail folder and select Properties / Previous Versions Tab.
b. After the list populates, select a version of the folder with a date and time prior to when the folders were deleted.
c. Click the Copy Button. In the Copy dialog box, select the Desktop or external device as the location to place the copied folder, or just use the restore tab in the previous versions window.
4. Use WLM import to retrieve the mails you lost if you saved them to an external device or desktop.
Hope this may be of help to you.
Don't forget to back up any new mails that have arrived in your account before doing this.