I believe I can pinpoint this a little more. I have found,
apparently, the blocked sender and probably safe sender
lists are maintained/saved UNTIL you close Outlook. Next
time you start it, the list/s are empty. I am leaving the
app open for a few days to verify this.

I am running 2007 version, original installation, not upgrade.

I tried to find out what format file this data is saved to, and where. No luck. It looks to me like MS is no longer supporting the 2007 version unless you pay.

Just verified that lists are saved on another computer with XP and a a laptop with Vista after they have been shut down and restarted.

This computer is dual boot XP/Windows 7. I normally use
the 7 most, but am going to shut down now and see what happens in XP , which is full and not just XP mode
within Windows 7.

After extensive trials, Outlook 7 loses names in Blocked Sender list when it is closed and/or computer is shut down with Outlook open. This applies only to Windows 7.
As long as Outlook remains open, names are retained in memory.

Same computer booted to XP does not lose names when Outlook is shut down or computer is shut down. A second computer with XP gives same results, as does a third computer with Vista. It seems to me that the problem is some kind compatibility issue between Outlook 7 and Windows 7. Anyone who solves this will make a lot of people happy.

Any ideas?

Hmm, and of course, I'm running Win7 64-Bit also.

I combined all my blocked senders into 1 list and then cleared and re-imported them into all my accounts.

I just finished adding about 7 blocked senders into the correct e-mail account and they didn't get added to the blocked senders list. I'll try what you did next time and see if they are there until I exit.

BTW, thanks for correcting my login stuff admin.

I did fail to mention that I am running 32 bit versions
of both operating systems. I have no idea what happens
with a 64 bit system.

I have not yet tried to export/import the sender files,
but will as soon as I get tired of finding the list gone after I shut down and restart!!!!

Well, as it turns out, I have 2 e-mail addresses that start with the same name from different isp's and I didn't have the correct one as the default.

My list of blocked is populating in the correct e-mail account, but not the others.

This is a real pain.