blend27 - 4:39 pm on Dec 14, 2012 (gmt 0)

Well, for one of my sites it seems like it started in 01-Nov-2012. This "compacted" dataset shows that different flavors of what seems to be IE7 from:

131.253.24.nnn
131.253.26.nnn
131.253.36.nnn
131.253.38.nnn

as mentioned before, the CSS and JS files are downloaded as well, the referrer provided appropriately, but not the images. Robots.txt file was not requested by any of mentioned below. Ecom Site. Requests are targeting pages that have product descriptions on them.

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2012-12-14 08:37:19.447 - 131.253.26.255 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SLCC1; .NET CLR 1.1.4325; .NET CLR 2.0.40607; .NET CLR 3.0.30729; .NET CLR 3.5.30707)
2012-12-14 01:54:37.393 - 131.253.24.128 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SV1; .NET CLR 1.1.4325; .NET CLR 2.0.40607; .NET CLR 3.0.30729; .NET CLR 3.5.30729; InfoPath.2)
2012-12-13 14:44:25.340 - 131.253.24.131 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SV1; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.648)
2012-12-13 13:52:29.877 - 131.253.36.202 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SLCC1; .NET CLR 1.1.4322; .NET CLR 2.0.40607; .NET CLR 3.0.30729; .NET CLR 3.5.30729)
2012-12-13 13:45:14.843 - 131.253.36.197 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SLCC1; .NET CLR 1.1.4322; .NET CLR 2.0.40607; .NET CLR 3.0.30729; .NET CLR 3.5.30707)
2012-12-13 12:43:27.140 - 131.253.26.226 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SLCC1; .NET CLR 1.1.4325; .NET CLR 2.0.40607; .NET CLR 3.0.30729; .NET CLR 3.5.30707; MS-RTC LM 8)
2012-12-13 12:05:53.787 - 131.253.26.233 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SV1; .NET CLR 1.1.4325; .NET CLR 2.0.50727; .NET CLR 3.0.04506.648)
2012-12-13 11:25:56.943 - 131.253.24.150 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SV1; .NET CLR 1.1.4325; .NET CLR 2.0.40607; .NET CLR 3.0.30729; .NET CLR 3.5.30707; MS-RTC LM 8)
2012-12-13 09:33:19.997 - 131.253.36.197 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SV1; .NET CLR 1.1.4325; .NET CLR 2.0.50727; .NET CLR 3.0.04506.648)
2012-12-13 08:26:15.720 - 131.253.24.141 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SLCC1; .NET CLR 1.1.4325; .NET CLR 2.0.50727; .NET CLR 3.0.04506.648)
2012-12-13 03:54:56.883 - 131.253.24.144 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SV1; .NET CLR 1.1.4325; .NET CLR 2.0.50727)
2012-12-13 03:10:12.420 - 131.253.36.200 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SLCC1; .NET CLR 1.1.4325; .NET CLR 2.0.50727)
2012-12-13 02:26:15.313 - 131.253.24.130 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SLCC1; .NET CLR 1.1.4325; .NET CLR 2.0.50727; .NET CLR 3.0.30729; .NET CLR 3.5.30707; MS-RTC LM 8)
2012-12-12 22:27:36.210 - 131.253.24.151 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SLCC1; .NET CLR 1.1.4325; .NET CLR 2.0.50727; .NET CLR 3.0.04506.648)
2012-12-12 19:47:47.253 - 131.253.36.204 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SLCC1; .NET CLR 1.1.4322; .NET CLR 2.0.40607; .NET CLR 3.0.04506.648)
2012-12-12 15:11:55.880 - 131.253.24.133 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SLCC1; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.648)
2012-12-12 14:14:49.460 - 131.253.26.231 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SV1)
2012-12-12 09:11:51.217 - 131.253.26.232 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SV1; .NET CLR 1.1.4322; .NET CLR 2.0.40607; .NET CLR 3.0.30729; .NET CLR 3.5.30729)
2012-12-12 04:56:55.743 - 131.253.24.136 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SLCC1; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.30729; .NET CLR 3.5.30729)
2012-12-12 04:30:23.843 - 131.253.26.249 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SLCC1; .NET CLR 1.1.4322; .NET CLR 2.0.40607; .NET CLR 3.0.04506.648)
2012-12-12 01:32:24.007 - 131.253.26.230 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SLCC1; .NET CLR 1.1.4325; .NET CLR 2.0.50727; .NET CLR 3.0.04506.648)
2012-12-12 00:55:01.580 - 131.253.26.255 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SLCC1; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.648)
2012-12-11 17:21:25.393 - 131.253.26.238 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SLCC1)
2012-12-11 10:02:23.043 - 131.253.24.158 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SLCC1; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.30729; .NET CLR 3.5.30707; InfoPath.2)
2012-12-11 02:28:32.473 - 131.253.26.225 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SV1; .NET CLR 1.1.4325; .NET CLR 2.0.50727; .NET CLR 3.0.30729; .NET CLR 3.5.30729; InfoPath.2)
2012-12-10 17:37:50.323 - 131.253.38.67 - Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Win64; x64; Trident/4.0)
2012-12-10 14:28:57.077 - 131.253.24.153 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SLCC1; .NET CLR 1.1.4322; .NET CLR 2.0.40607; .NET CLR 3.0.04506.648)
2012-12-10 03:29:43.270 - 131.253.36.197 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SV1; .NET CLR 1.1.4322; .NET CLR 2.0.40607)
2012-12-09 18:04:13.223 - 131.253.24.154 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SV1; .NET CLR 1.1.4322; .NET CLR 2.0.50727)
2012-12-09 17:37:24.997 - 131.253.26.232 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SLCC1; .NET CLR 1.1.4322; .NET CLR 2.0.40607; .NET CLR 3.0.30729; .NET CLR 3.5.30707; MS-RTC LM 8)
2012-12-09 17:16:24.897 - 131.253.24.148 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SLCC1; .NET CLR 1.1.4322; .NET CLR 2.0.40607; .NET CLR 3.0.30729; .NET CLR 3.5.30707; InfoPath.2)
2012-12-09 11:46:05.007 - 131.253.24.151 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SV1; .NET CLR 1.1.4322; .NET CLR 2.0.40607; .NET CLR 3.0.04506.648)
2012-12-09 03:57:49.447 - 131.253.24.150 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SV1; .NET CLR 1.1.4325; .NET CLR 2.0.50727; .NET CLR 3.0.04506.648)
2012-12-09 01:18:50.337 - 131.253.24.156 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SV1; .NET CLR 1.1.4325; .NET CLR 2.0.50727; .NET CLR 3.0.30729)
2012-12-08 23:33:02.073 - 131.253.26.231 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SLCC1; .NET CLR 1.1.4325; .NET CLR 2.0.40607; .NET CLR 3.0.04506.648)
2012-12-08 21:59:09.773 - 131.253.24.141 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SV1; .NET CLR 1.1.4322; .NET CLR 2.0.40607; .NET CLR 3.0.04506.648)
2012-12-08 21:42:57.883 - 131.253.24.158 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SLCC1; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.30729; .NET CLR 3.5.30729)
2012-12-08 21:40:38.590 - 131.253.26.224 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SLCC1; .NET CLR 1.1.4325; .NET CLR 2.0.50727; .NET CLR 3.0.30729)
2012-12-08 19:44:28.330 - 131.253.26.253 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SLCC1; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.648)
2012-12-08 16:16:15.100 - 131.253.24.142 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SLCC1; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.648)
2012-12-08 13:52:11.617 - 131.253.24.149 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SV1; .NET CLR 1.1.4325; .NET CLR 2.0.40607; .NET CLR 3.0.30729; .NET CLR 3.5.30707)
2012-12-08 13:33:18.543 - 131.253.36.200 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SLCC1; .NET CLR 1.1.4325; .NET CLR 2.0.40607; .NET CLR 3.0.04506.648)
2012-12-08 12:40:17.157 - 131.253.26.230 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SLCC1; .NET CLR 1.1.4325; .NET CLR 2.0.40607; .NET CLR 3.0.04506.648)
2012-12-08 08:48:16.660 - 131.253.26.222 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SV1; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.648)
2012-12-08 07:45:26.550 - 131.253.24.159 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SLCC1; .NET CLR 1.1.4325; .NET CLR 2.0.50727; .NET CLR 3.0.30729)
2012-12-08 04:07:54.713 - 131.253.26.229 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2)
2012-12-08 03:48:08.217 - 131.253.26.239 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SLCC1; .NET CLR 1.1.4325; .NET CLR 2.0.50727; .NET CLR 3.0.04506.648)
2012-12-08 02:40:16.970 - 131.253.24.154 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SV1; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.30729; .NET CLR 3.5.30729; MS-RTC LM 8)
2012-12-08 01:09:03.220 - 131.253.24.153 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SLCC1; .NET CLR 1.1.4325; .NET CLR 2.0.40607; .NET CLR 3.0.30729)
2012-12-07 23:57:09.923 - 131.253.24.154 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SLCC1; .NET CLR 1.1.4322; .NET CLR 2.0.40607; .NET CLR 3.0.30729)
2012-12-07 20:14:53.127 - 131.253.24.145 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; SV1; .NET CLR 1.1.4325; .NET CLR 2.0.50727; .NET CLR 3.0.30729)
2012-12-07 17:22:34.877 - 131.253.26.254 - Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; SV1; .NET CLR 1.1.4325; .NET CLR 2.0.50727; .NET CLR 3.0.30729; .NET CLR 3.5.30729; MS-RTC LM 8)
2012-12-02 21:28:52.697 - 131.253.38.67 - Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Win64; x64; Trident/4.0)
2012-11-25 13:54:42.900 - 131.253.38.67 - Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Win64; x64; Trident/4.0)
2012-11-17 08:47:04.720 - 131.253.38.67 - Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Win64; x64; Trident/4.0)
2012-11-08 15:03:47.863 - 131.253.38.67 - Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Win64; x64; Trident/4.0)
2012-11-01 11:53:26.340 - 131.253.38.67 - Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Win64; x64; Trident/4.0)

I'll dig into Headers sent a bit later.