Sending to a mailing list not working properly

I have Windows 7 64 bit and am using Windows Live Mail.  Something is wrong with my email contacts!

Have 24 different categories and close to 700 email contacts.  When I rebuilt my computer after frying the hard drive and replacing it, brought in an old contact list of 4 1/2 years ago, because the Dell DataSafe software that I had everything backed up on didn't bring the email addresses back.

Now the email list is First Name, Last Name and Email Addresses.  When I put 43 of the email addresses into one of the categories and went to send the same email to all of them, it froze and I lost the 1/2 hour of work.  Then, when I looked at that category, it showed the 43 email addresses, but when I started a new email for that category (and hit the plus sign-next to the category name), only 11 of the 43 email addresses were at the top of the email message I had hoped to send.

I went on the web, to no avail for help.  When I went back to that category, it showed the 43 email addresses and I started a new email and there aren't any email addresses at the top of the message after hitting the + sign next to the category name!  I'll bet I have spent over 50 hours rebuilding my email list and now I can't even send a blast to 43 people at once!

What can I do to correct this?

Also, how can I get a copy of those 700 email addresses in another file, in case my computer crashes again?

Thanks in advance!  Jim G

[Original title: WLM Contacts]