Hello!
My server returns me a strange undocumented error. I have IIS 8.5 and pages with multiple image thumbnails. For start, here is IIS log:
2016-09-06 10:24:03 192.168.169.253 GET /3dModels/Webgl/bfd414ba72b84478/thumbnail.png - 80 - 256.256.256.256 Mozilla/5.0+(Windows+NT+10.0;+WOW64)+AppleWebKit/537.36+(KHTML,+like+Gecko)+Chrome/53.0.2785.89+Safari/537.36 http://server.example.com/WebModels 404 502 0 46 2016-09-06 10:24:03 192.168.169.253 GET /3dModels/Webgl/b05e8a3f5b634244/thumbnail.png - 80 - 256.256.256.256 Mozilla/5.0+(Windows+NT+10.0;+WOW64)+AppleWebKit/537.36+(KHTML,+like+Gecko)+Chrome/53.0.2785.89+Safari/537.36 http://server.example.com/WebModels 404 502 0 62 2016-09-06 10:24:03 192.168.169.253 GET /3dModels/Webgl/adb7ebeeb4554dd8/thumbnail.png - 80 - 256.256.256.256 Mozilla/5.0+(Windows+NT+10.0;+WOW64)+AppleWebKit/537.36+(KHTML,+like+Gecko)+Chrome/53.0.2785.89+Safari/537.36 http://server.example.com/WebModels 404 502 0 78 2016-09-06 10:24:03 192.168.169.253 GET /3dModels/Webgl/92fada3f39254a7a/thumbnail.png - 80 - 256.256.256.256 Mozilla/5.0+(Windows+NT+10.0;+WOW64)+AppleWebKit/537.36+(KHTML,+like+Gecko)+Chrome/53.0.2785.89+Safari/537.36 http://server.example.com/WebModels 404 502 0 78
Requested PNGs are 100% accessible through browser (I can open link in new tab). Every reload generates few of 404 on various PNGs. Which PNGs get 404 and count of PNGs with 404 are random. Funny think is when I disable cache in developer tools, all images are loaded correctly.
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Do you have any idea what causes this problem? Thanks!
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