BleepingComputer.com: Cannot open Outlook email

I can open emails in Outlook 2003 under my user name. However, when my wife logs in under her name she can no longer gain access to her mail server. Here is the error message

Unable to open your default email folders. File access is denied. You do not have the permission required to access the file.

C:/Users/Mugsy/AppData/Local/Microsoft/Outlook/Outlook.pst

I am the user Mugsy and the archive.pst and outlook.pst files are in the Mugsy account. There are no issues with that user. However, under my wifes user name there are no .pst files in Outlook. This is a very recent issue. All windows updates are current. Anti virus(norton) and spy bot were all updated earlier this evening.

Don't know where to start here, any direction would be greatly appreciated.

Hi Mugsy,

Hope this will help you on your matter.

Your Windows Mail does not have all of its defaults assigned.
Go to Default Programs, which you can access either from the Start
menu or via the Control Panel, then click the first item: "Set your default
programs."
After a few seconds, a list of programs comes up. Click on Windows Mail.
If it doesn't respond with "This program has all its defaults" then fix it by
clicking on the option indicated by the first green arrow

Thanks very much for your reply. Following your directions I can successfully convert to Windows Mail, however that is not the mail carrier that I have been using.
I was using Outlook with no previous issues, until I posted my recent problem.
I tried setting the defaults with Outlook, but I continue to receive the same error message.

I found a solution.
Went to control panel>mail>show profiles>removed the profile listed>added %username%
I am now able to get into outlook and receive emails. still testing to see if I can send, but that issue is resolvable now that I can get into Outlook