I noticed that Google Webmaster Tools shows a lot of crawling errors. Mostly 403 because of wrong URLs.
http://www.example.com/assets/Uploads/Directory/pdf-file.pdf (what WT shows/recognized)
http://www.example.com/assets/Uploads/directory/pdf-file.pdf (what I see on the website and how the folder is named)
There are a lot of those errors. Some folders seems to be upper case instead of lower case. But I have never used UC letters and I have checked the website regularly. It only occurs in downloads not pages.
Maybe this is a Google error. But I wanted to ask if there are known issues.