Let's get one thing out of the way, i.e. account vs profile. as far as my wife is concerned, since I am home, and have the time, and she works, she not only does not mind, but urges me to check her mail. So, there is no reason to have a separate profile. Now, a profile could be in the same Windows folder as yours, or in a separate Appl.Data folder. In this case the paths would be:C:\Documents and Settings\user_name\Application Data\Thunderbird\Profiles
C:\Documents and Settings\user_name1\Application Data\Thunderbird\Profiles
and you would be "user_name", and your wife would be "user_name1". This will be for maximum privacy. Each one of you logs in separately, and each one would have a separate folder. It does not seem to be that way, and if all folders are in "user_name", then we dealing with separate accounts, which may not allow privacy, but it is simple to deal with.
Assuming the simpler case, your mail is going to be in C:\Documents and Settings\user_name\Application Data\Thunderbird\Profiles\xxxxx.Thunderbird\Mail\pop.isp.net, while your wife's mail will be in:C:\Documents and Settings\user_name\Application Data\Thunderbird\Profiles\xxxxx.Thunderbird\Mail\pop.isp-1.net. Two separate folders which would have their own pairs of files, i.e. Inbox and Inbox.msf, etc. If you copied the old Inbox without renaming it, you would replace the contents of your present Inbox, but you say that nothing was transferred. To me, it means that it was pasted in the wrong folder. Renaming a file like Inbox is done by right clicking on the old Inbox, and renaming it Oldinbox, or anything you want, then right click|copy the renamed file (Oldinbox, now), finally deposit it in correct folder, by right clicking|paste. When you reopen Thunderbird, which was closed while you all that, you will find an Oldinbox folder.
Are you doing things which way?
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