Master Page Changes Not Being Reflected

Question

I have a site collection and various levels of sub sites that are using a custom master page from the site collection's master page gallery (as well as a custom CSS, theme and background image file).

I would like to add some CSS and JavaScript to the master page so it is reflected in all sites under the site collection.

Problem is my changes (made in SharePoint Designer) are not being reflected. Even changes to the CSS file are not being reflected.

However, when I do make changes, I can see in the master page gallery that the Modified field is changing correctly, and so too the file size.

I have confirmed that this is indeed the master page that is being used by checking the webs' master page URL: Get-SPSite | Get-SPWeb | % {"Site: " + $_.Url + " Master: "+ $_.MasterUrl}

There is a custom Composed Look that has been created that uses this master page (and the other files mentioned above). Interestingly, I'm not able to change to a different composed look because I get a "Error in the application" error.

I do not have publishing enabled on the site collection, so can't "publish a major version", as I've read being suggested elsewhere.

I have also discovered that this branding was developed as a custom solution by my predecessor, deployed at site collection scope, but it has been set to hidden. I have confirmed this with Get-SPFeature | Sort -Property Scope,DisplayName | FT -GroupBy Scope DisplayName,Id

Answer 1

What SharePoint version you are using? My gut feeling is that there is something on that custom solution that might be overriding your changes. Is there any chance that you can have a look at the source files to see what it is doing.

Answer 2

Problem solved.

I had to allow master page changes from SharePoint Designer from site collection settings > SharePoint Designer Settings > check Enable Customizing Master Pages and Page Layouts.