Stuart did the links work before the https was turned on, or was that not possible at any point?

I would double-check the handler in the web.config file in case it has been removed or the spelling changed accidentally. 

If that doesn't work it shouldn't be too hard to test out whether this is a built-in issue by setting a localhost setup to use https.

Stuart,

If the site is running on IIS 7 or 7.5 in an ASP.Net 4.0 application pool, please check that the LinkClickHandler registration in the <system.webServer><handlers> section of web.config has been properly modified to remove the ASP.Net 2.0 preCondition attribute:

<add name="LinkClickHandler" path="LinkClick.aspx" verb="*" type="DotNetNuke.Services.FileSystem.FileServerHandler, DotNetNuke" preCondition="integratedMode,runtimeVersionv2.0" />

the ",runtimeVersion2.0" portion of the preCondition value should be removed from all handler registrations in this section becoming:

preCondition="integratedMode"

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Bill, WESNet Designs
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