Ok thanks for reporting, will give it a go and see if I can reproduce

Just tried with a fresh install and it works fine... does this happen with all less files, what happens if you try the following snippet

@base: #f938ab;

.box-shadow(@style, @c) when (iscolor(@c)) {
  -webkit-box-shadow: @style @c;
  box-shadow:         @style @c;
}
.box-shadow(@style, @alpha: 50%) when (isnumber(@alpha)) {
  .box-shadow(@style, rgba(0, 0, 0, @alpha));
}
.box {
  color: saturate(@base, 5%);
  border-color: lighten(@base, 30%);
  div { .box-shadow(0 0 5px, 30%) }
}

So I think there might be an error in you less file , but running that example snippet should give us an idea of that (if that works it is ...)

It's all Less files, also one containing only your snippet.

Maybe it's something related to folder permissions, but I would not know what as it's been possible to install Umbraco with packages.

This is what we are seeing

http://prntscr.com/8yy712

There is no entries in the trace log at save time, and no new entries is added after saving the Less files and getting that message.

Yeah unfortunately the error message doesn't give us that much information, any chance you can send a copy of the site and db? Then I can debug locally... you can send to tim at nibble dot be

$@&%*!

Looked in web.config, and several sections and entries was missing.

We did upgrade from 7.3.0 to 7.3.1, to fix the error where you were not able to save save Partial Views more than once without having to refresh.

But the error was present before the upgrade, so something must have happened in the initial install.

I added the missing sections and entries, and now it works!

Thanks for your help, probably would not have spotted it without your suggestion.

Great, glad it's solved! :)

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