This sounds similar to some problems I've hit occasionally where it's a case of the browser caching the old version of scripts and CSS. Imagine you've got app.css as the main stylesheet for concrete5's interface - that's going to be completely different in v8, but if your browser is hanging on to the old one its going to go all screwy.

Doing a complete hard refresh may help (shift + refresh in Chrome tends to work well), or even clearing your browser cache.

Some servers are set up to tell browsers not to cache anything, while others have quite aggressive caching defaults. You could even try a completely different browser.

Thank you for your fast response.

All my browsers empty cache on closing. I was manually emptying server and browser caches. Same result.

Firefox is in this case is behaving the worst. Block icons will not be displayed in viewing mode. Opera and Chrome display the page. But none is showing icon in the backend. Toolbars are filled with blanks.

I am trying to find more hints...

With the login you sent through earlier I'm able to log in and edit without any missing icons, not seeing any missing files or otherwise.

This is a 5.7 install though, are you able to install a fresh v8 copy and send through those details?

Sorry, I was messing with the server too much, things went out of control.
It took some time to fix it. (That's why I had to 'dis'-publish my post from earlier, not to embarrass myself too much)

The latest trial was to enhance update directory permission to 777.
No luck. So I've reversed it back to 755.
Now you will find a fresh upgrade of 8.1 installed.
Including the problem.

Here are login details again (which will be available for a testing period only)
(Login deleted due to solved problem)

I was trying to re-run the installation script
http://[sitename]/bugtest/index.php/ccm/system/upgrade?force=1......

I would like to really thank you for your efforts.

There might be a large time difference. My local time is GMT+1. Sorry for any delays.

Strange one this.

Take for example this file here on a 8.1 site:
http://www.annaglenn.com.au/concrete/blocks/content/icon.png...
No problems loading

On your site everything is running out of the updates folder (which is fine), so stylesheets are loading here for example:
http://koeber.it-wf.de/bugtest/updates/concrete5-8.1.0/concrete/css...

But if we try to view that icon file in this page:
http://koeber.it-wf.de/bugtest/updates/concrete5-8.1.0/concrete/blo...
We get a broken image. Firefox actually says "The image .. cannot be displayed because it contains errors"

I actually looked in both files, the working and the broken one in a text editor. The files have _similar_ content, but they're not identical.

It's almost like your server is breaking the output of images, or that some of the image files have been corrupted via upload or otherwise.

I couldn't quite work out why, the only thing I noticed is that your server appears to be running Varnish cache - I'd advise turning that off.

To test this, I have just replaced the image using FTP set to binary mode at..

http://koeber.it-wf.de/bugtest/updates/concrete5-8.1.0/concrete/blo...

I have replaced the font files as well...

Seems to be much better now.
My best advice would be to replace the entire 5.8.1 folder and its contents with one that has been uploaded in binary mode..
Or...
If you have control panel access, upload the zipped file and unzip it on the server, this will avoid any file corruption caused by FTP and is much faster..

That's incredible. I'm speechless.

I would never have guessed that it was down to ftp-settings.
(Although I was starting to eyeballing different ftp-clients.)

I was testing it: Spot on !!! Worked every time.

The Problem got solved so fast, which I probably wouldn't have found out on my own.
This community is brilliant.

Thank you all, especially the people involved on both sides of the planet and working together so amazingly well.