For years (if not decades) case haven’t been important in file names nor URL in the Microsoft world (using web server on a MS computer will result as this exact experience concerning letter case. An Image.jpg or IMAGE.JPG will only show one of the two images).
SMTP RFC 2821 says that the local part of the email address is case sensitive. Some ignore this and consider upper and lower case the same.
Section 2.4:
> The local-part of a mailbox
MUST BE treated as case sensitive. Therefore, SMTP implementations
MUST take care to preserve the case of mailbox local-parts. Mailbox
domains are not case sensitive.
What it means is, a mailserver should resolve local part case-insensitively, so that Bob@example.com and bob@example.com end up in the same mailbox.
But, to be spec-compliant, a mailserver MUST send on an email addressed to AlIcE@example.net to AlIcE@example.net, exactly, without downcasing it to alice@example.net.
I'd imagine this is often honored in the breach, but there you have it.
> There were four test URLs in total, two of which tested for how search engines deal with unique content
...
> There is one unusual thing, however – a site: search brings up the lowercase URL, but the uppercase URL is filtered out for being too similar to the other displayed URLs and isn’t shown unless the ‘repeat the search with the omitted results included’ link is clicked.
Maybe the content isn't unique enough so Google's duplicate detection algorithm marks them as duplicate?
The two examples contain similar keywords and don't seem to have any outgoing links. A human would probably flag them as spun articles so I wouldn't be surprised if Google did the same.
Maybe the results would be different if each link was a unique high quality article instead.
> Monitoring the server logs showed that Bingbot only crawled the lowercase version of the URL.
I've always thought it was much more common that sites written in ASP.Net have case-sensitive URLs. At least that was quite common ~5 years ago (was it a default setting or something? I haven't done .Net stuff in a while). So it's pretty crazy that Bing only crawls lowercased URLs.
Would have been interesting to see how case differences in the host name portion of the URL were treated. Domain names are case insensitive — would google search both https://foo.example.com/bar and https://foo.Example.com/bar? It should not.
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[ 2.4 ms ] story [ 33.7 ms ] threadCould this be an extension of that ? Looks like.
SMTP RFC 2821 says that the local part of the email address is case sensitive. Some ignore this and consider upper and lower case the same.
Section 2.4:
> The local-part of a mailbox MUST BE treated as case sensitive. Therefore, SMTP implementations MUST take care to preserve the case of mailbox local-parts. Mailbox domains are not case sensitive.
What it means is, a mailserver should resolve local part case-insensitively, so that Bob@example.com and bob@example.com end up in the same mailbox.
But, to be spec-compliant, a mailserver MUST send on an email addressed to AlIcE@example.net to AlIcE@example.net, exactly, without downcasing it to alice@example.net.
I'd imagine this is often honored in the breach, but there you have it.
An MDA Mail Delivery Agent or LDA Local Delivery Agent inside a domain can choose whether to be case sensitive, but is discouraged from doing so.
The same issue exists for dots '.' in local part.
I've certainly strtolower'ed some email inputs...
...
> There is one unusual thing, however – a site: search brings up the lowercase URL, but the uppercase URL is filtered out for being too similar to the other displayed URLs and isn’t shown unless the ‘repeat the search with the omitted results included’ link is clicked.
Maybe the content isn't unique enough so Google's duplicate detection algorithm marks them as duplicate?
The two examples contain similar keywords and don't seem to have any outgoing links. A human would probably flag them as spun articles so I wouldn't be surprised if Google did the same.
Maybe the results would be different if each link was a unique high quality article instead.
I've always thought it was much more common that sites written in ASP.Net have case-sensitive URLs. At least that was quite common ~5 years ago (was it a default setting or something? I haven't done .Net stuff in a while). So it's pretty crazy that Bing only crawls lowercased URLs.
But it might cause problems if the IIS server isn't properly case-preserving to normalize back to the standard (possibly capitalized) form.
Mac filesystem was nicely case-preserving but case-agnostic in this way, going back decades.
Now I either 301 redirect to the proper-case url or ensure I have canonical tags set up.