I use XP service pack 3 and am having trouble with my outlook express.  When I click send and receive and want to send or receive from my pop3 program, which is gmail, I get a prompt for a logon, including user name and password.

 There is already one written in there.  But when I click enter it just goes and comes back again.

 I just came back from a 40 day trip where I was using my laptop. I didn't have this problem before.  When I came back, I had this problem, and also I couldn't access my gmail account on my PC either.  So I changed my password on my gmail account and now I can access this on the web. And, I changed the password for my gmail account in my Outlook express as well, but I'm still not able to send or receive from my pop3 (gmail) program from OE as before.

 Can you please help as I use this account for my online teaching and need to have all my letters in my OE where I can read them OFFLINE as well.

Thank you.
Dr.DWell, I suggest you try simply double-checking the password in OE.  Of course, make sure your CAPS Lock is not on unless you intended to use CAPS. 

What error MESSAGE do you get when trying to send/receive with OE?

I suggest you review all settings in your gmail email account in OE.  Do you know where to find that info on GOOGLE's website?  Also, logon to gmail VIA your web browser and verify that POP mail is still enabled there.  Based on what you've said, it seems POSSIBLE someone gotten your previous password, accessed your email account, and may have changed some online settings.