Support

Yesterday afternoon when I logged into my site’s backend very little works. The front end seems to be unaffected. I can get to home dashboard but the only button that works at the top is the one that takes you to the front end. I can’t even log out as the user menu doesn’t work. On the left side bar, the only one that works is system and that gives a very different view to normal. From there I can get to global configuration but that only has the site tab and the save buttons don’t work.















 
Using inspect I found 
 

class="js_modInvalidatecach header-item-content" title="Invalidate Cache" data-token="0b10f9aee99d933673c5bfaa50c08a21" data-url="https://---.com/" disabled><div class="header-item-icon" aria-hidden="true"><div class="w-auto"><svg aria-hidden="true" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 297 297" style="width: 1rem; height:1rem; fill: currentColor"><title>Bin</title><defs/>
<path d="M216.979 150.445c-24.601 0-44.615 20.014-44.615 44.615s20.014 44.615 44.615 44.615c24.6 0 44.615-20.014 44.615-44.615s-20.014-44.615-44.615-44.615zm21.889 56.965a6.747 6.747 0 010 9.539 6.729 6.729 0 01-4.769 1.975 6.729 6.729 0 01-4.769-1.975l-12.35-12.35-12.35 12.35c-1.317 1.316-3.044 1.975-4.769 1.975s-3.452-.659-4.769-1.975a6.747 6.747 0 010-9.539l12.35-12.35-12.352-12.35a6.747 6.747 0 010-9.539 6.749 6.749 0 019.539 0l12.35 12.35 12.35-12.35a6.749 6.749 0 019.539 0 6.747 6.747 0 010 9.539l-12.35 12.35 12.35 12.35zM227.354 59.832c-.001-10.822-8.806-19.626-19.628-19.626H55.033c-10.822 0-19.626 8.804-19.626 19.626v18.244h191.948V59.832zM216.979 136.957c1.233 0 2.454.052 3.668.128l2.716-45.521h-47.368v62.351c10.515-10.473 25.004-16.958 40.984-16.958zM103.885 13.488h54.99v13.229h13.488V6.744A6.743 6.743 0 00165.619 0H97.14a6.743 6.743 0 00-6.744 6.744v19.973h13.488V13.488z" />
<path d="M175.994 273.748c0 5.393-4.372 9.764-9.764 9.764a9.763 9.763 0 01-9.764-9.764V91.564h-50.173v182.184c0 5.393-4.372 9.764-9.764 9.764a9.763 9.763 0 01-9.764-9.764V91.564H39.398l11.881 199.094A6.744 6.744 0 0058.01 297h146.739a6.744 6.744 0 006.732-6.342l2.243-37.591c-14.686-.815-27.934-7.104-37.73-16.862v37.543z" />
</svg></div></div><div class="header-item-text">Invalidate Cache</div></a></div><div class="header-item"><a href="https://www.akeeba.com/https://---.com/" class="header-item-content" title="Open frontend of --- in a new window." target="_blank">
<div class="header-item-icon">


 









To recover I took the latest backup and restored to a different subdomain. on that recovered site I regenerated a .htaccess file from admin tools and that worked fine. I copied the .htaccess file generated in the recovered site to the broken site and that worked.
 
I am attaching a copy of the .htaccess file which breaks the backend. 
 
I have been using admin tools or many hears and this is the first time generating a .htaccess has caused problems. It is most likely i have done something wrong and like to know what that is.
 
thnaks you.
 

Thank you Nicholas, I will look closely at that and try better to understand, relieved that is is my error.