Request For Network Password

[Questman]

I have a laptop which using Windows 7.
I use Outlook for my emails and have accounts set up with TalkTalk etc.
For the last few days I have being inundated with a window menu appearing on screen regardless of what I am doing which says Enter Network Password and Type in your username and password although both appear in the window. Then it appears asking for my wife's details likewise.
Anyone know what causes this and how I can stop it?
Thanks.

[ChuckFickens]

try changing the logon network security authentication settings for the "etc" accounts to NTLM or negotiate instead of anonymous in outlook.