Access hidden Office 365 Sharepoint Online site locations with windows explorer.

When you open a site in windows explorer, you’re actually exposing the root of the site which can be useful if you need to add a file to the root or view your sitemap etc. Frustratingly though, Msft has hidden various directories from view. The _catalogs directory, for example, which contains all the critical stylesheets, master pages etc can’t be accessed this way. If you don’t want to struggle with Sharepoint Designer, here’s a trick to reveal all user accessible files in explorer:Open network places (or location or whatever your os calls it) and click “add a network place”
TIP: if you get an access denied error, make sure you’re logged in via IE.

To access the root of the site:

Enter https://-public.sharepoint.com/

For a specific directory:
Enter https://-public.sharepoint.com/_catalogs
For a 2013 site you’ll then need to open the master page directory and select the folder for your region (eg en-us)
Once you’ve established a network place you can navigate to it and open the css files in notepad.
After making your changes, you will have to save the file locally, open 2 explorer instances and drag it over to the appropriate sharepoint directory because you can’t save directly to sp (for some reason).
Now you can work directly with critical site files without having to deal with the perennial browser glitches and slowness of the user interface.
Questions?

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