When OE crashes or won't start

Most crashes and failed starts are the result of one or more of OE's *.dbx files being damaged, or being marked as Read-only. So begin trouble-shooting by verifying none are marked as Read-only.
Close OE and open the store folder in Windows Explorer.
Select all files (Edit Select All, or CTRL-A), then right-click on any selected file and select Properties. Clear the checkbox for the Read-only attribute.
If OE will start, try compacting all your folders as this often repairs minor damage.
Click File Work Offline so that no new messages will be arriving.
In the Folder list, click on Outlook Express so that no folder or newsgroup is open, then close the Folder list (View Layout).
Click File Folder Compact All Folders. Do not use your computer until the process is complete, which might take several minutes. If an error occurs, close OE, re-open it, and begin the process again from the top. If the same error occurs again, close OE, restart your computer (or logoff and then logon again), open OE and then begin the whole process again.
If Outlook Express will not start, move the *.dbx files from your store folder and into a new empty folder.
Download this small script that will open the store folder of the currently logged-on Identity. Alternatively you can find it be searching in Windows Explorer for files named *.dbx. Be sure to include hidden files in your search, as OE user files are marked as hidden by default. To view hidden files:
In Windows Explorer, click Tools Folder Options then click theView tab.
Click the button for Show hidden files and folders.
On your desktop, right-click and point to New Folder.
In the store folder window, click Edit Select All, or press CTRL-A.
Drag the selected files and drop them into the New Folder on your desktop.
Try opening OE again. If it starts without error, try importing your mail folders.
Click File Import Messages Microsoft Outlook Express 6.
Select Import from a store folder and click Browse.
Navigate to the New Folder on the Desktop.
If OE cannot import the mail folders, it means the file Folders.dbx is probably damaged. In that case, close OE and move all the other *.dbx files back into the store folder. When you re-start OE, it will build a new index of all the *.dbx files it can read, and create a new Folders.dbx. Understand though that you will lose the mail tree structure, all lists of newsgroups, and all synchronization options, and that message rules will likely need to be edited.

If any *.dbx file fails to be imported, you can buy DBXtract or download the free Macallan Outlook Express Extraction in order to extract individual *.eml files for each message it finds in the damaged *.dbx file. You can then drag those *.eml files and drop them into an OE mail folder in the OE Folder list.
If you still cannot start OE, your Identity in the registry is probably damaged.
Download the Force Identity Logon script.
Run the script to access the Identities Manager.
Create a new Identity, then switch to it when prompted.
If you have previously exported your accounts settings to Internet Account files (*.iaf), cancel the Add Account wizard that will start automatically. Then click Tools Accounts and use the Import button to import each of your exported *.iaf files.
If you have not previously exported your account settings, follow the wizard to set up your basic email account.
If you cannot run the Identities Manager and OE still will not start, the damage in the registry is more extensive and requires more drastic steps. Open Regedit and export the entire HKCU\Identities key, then delete it. Double-click the saved *.reg file you exported and then try opening OE. If OE still fails to open, export each sub key HKCU\Identities\{GUID} sub-key to its own *.reg file, then delete the entire HKCU\Identities key again. Double-click each of the GUID *.reg files and then Open OE. The New Account wizard will begin, but just click cancel, as you are going to bypass this first default Identity. Click File Identities Manage Identities and try switching to your old Identity. If this is successful, you can then delete the new empty Identity from the Manage Identities dialogue. If this fails and OE will still not start, you will have to again delete the HKCU\Identities key, open OE, set up a new Identity and import your mail folders from the previous Identity. More information, including detailed instructions, can be found in the MS Knowledge Base article Cannot Start Outlook Express .