Server's host key does not match

Ever since recently changing passwords on Version 5.1.5, I have been getting a "Potential Security Breach" error warning every time I try to login. (Screen capture attached.) I have tried both the Update and Add buttons, but the warning appears next time anyway.

Once I get in, everything looks and works normally. How can I remove this inconvenience? Thanks.

Tom Gillman

robots.txt;-;28;2013-01-31T04:53:07.000Z;"auldtom" [3800769];"www" [15000];rw-r--r--;0
prussian.jpg;-;1242;2014-01-01T19:56:52.000Z;"auldtom" [3800769];"www" [15000];rw-r--r--;0
cgi-bin;d;4096;2013-08-07T12:21:30.000Z;"auldtom" [3800769];"www" [15000];rwxr-xr-x;0
403.shtml;-;297;2013-01-31T04:49:59.000Z;"auldtom" [3800769];"www" [15000];rw-r--r--;0
500.shtml;-;297;2013-01-31T04:48:50.000Z;"auldtom" [3800769];"www" [15000];rw-r--r--;0
php;d;4096;2013-06-11T00:52:25.000Z;"auldtom" [3800769];"www" [15000];rwxr-xr-x;0
secure;d;4096;2014-03-20T16:21:47.000Z;"auldtom" [3800769];"www" [15000];rwxr-xr-x;0
pantone_273.jpg;-;1243;2014-01-01T19:53:45.000Z;"auldtom" [3800769];"www" [15000];rw-r--r--;0
aspen;d;4096;2013-06-08T05:22:04.000Z;"auldtom" [3800769];"www" [15000];rwxr-xr-x;0
christmas_2013.html;-;4458;2013-12-30T16:06:04.000Z;"auldtom" [3800769];"www" [15000];rw-r--r--;0
.htaccess;-;142;2014-05-14T02:21:55.000Z;"auldtom" [3800769];"www" [15000];rw-r--r--;2
classroom strategies 2009.pptx;-;1621989;2014-04-01T18:35:19.000Z;"auldtom" [3800769];"www" [15000];rw-r--r--;0
1285161769_409573_bb_testbank.zip;-;7778968;2014-04-18T00:20:49.000Z;"auldtom" [3800769];"www" [15000];rw-r--r--;0
Startup conversation with host finished.

Is the fingerprint changing with each login or is it the same? Can you attach complete logs from two consecutive sessions using the latest version of WinSCP.