The content from the content blocks reappeared again and since I was still getting the fatal error when I went back down to 5.4.1, I upgraded again. I looked in the models folder where the error says it is being generated but the folder was empty. Should there be something in there? Help someone!!!

try not upgrading via simplescripts, concrete5 works fine without simplescripts, and there have been problems in the past with it,

I restored the backup for 5.4.1 through Simple Scripts. Then downloaded 5.4.1.1 directly from the Concrete5 website. I installed the "concrete" subfolder as directed and followed the upgrade steps. I still have the same fatal error message in the File Manager (Fatal error: Cannot make static method AttributeKey::getList() non static in class FileAttributeKey in /home1/mkwebcon/public_html/stclementmo/concrete/models/file_attributes.php on line 241) When checking the models folder, there is no file named "file_attributes.php".

Help please!!!

It's very disappointing that no one can help me with this problem. All I did was a simple upgrade and now I can't access the File Manager due to a fatal error. Seems to me that Concrete5 is a fatal error. I'm going to have to start looking for other CMS software that has better support.

I would suggest doing a fresh install of 5.4.4.1 only in a sub directory and see if that works.

and not through simple scripts.

I experience exactly the same problem, after upgrade to v5.4.1.1. Any suggestions? I use Mac OS X ver 10.6.6. The same error appears in Safari ver 5.0.3 and Firefox ver 3.6.8. I'm NOT using SimpleScripts.

I have tried a clean install (empty directory, empty database) of 5.4.1.1 on my platform and then everything works OK, so something happened in the upgrade.

I've also tried a clean install of v5.4.1 that I then upgraded to v5.4.1.1, but that did not recreate the problem.

I've found a workaround.

I just renamed the concrete directory to concrete.old and then simply uploaded the concrete directory from the distribution (as when doing a manual upgrade), and viola, the file manager appeared as normal.

I have two separates site I maintain, on separate domains. I had the same problem on both but the solution also worked on both.

I've already uploaded the 5.4.1.1 concrete folder. I'm not seeing how changing the name to add old and uploading it a second time will make any difference. What am I missing?

Well, it should of course not change anything, but it seems that something is corrupted after having done the first upload and run the update procedure, so a second upload of the concrete folder (and no update procedure) made both my sites work. But don't ask me why ;-).

I tried the workaround suggested. Renamed concrete sub-directory to concrete-old. Downloaded a fresh version again from Concrete5. Uploaded the new concrete sub directory folder. Went back to Dashboard login and could not get into Dashboard or to Website. Received the following fatal error.
Warning: require_once(Zend/Cache/Backend/File.php) [function.require-once]: failed to open stream: No such file or directory in /home1/mkwebcon/public_html/mywebsite/concrete/libraries/3rdparty/Zend/Cache.php on line 132

Fatal error: require_once() [function.require]: Failed opening required 'Zend/Cache/Backend/File.php' (include_path='.:/usr/lib64/php:/usr/lib/php:/home1/mkwebcon/public_html/mywebsite/libraries/3rdparty:/home1/mkwebcon/public_html/stclementmo/concrete/config/../libraries/3rdparty') in /home1/mkwebcon/public_html/mywebsite/concrete/libraries/3rdparty/Zend/Cache.php on line 132

Any ideas how to fix this fatal error? Or is the problem bigger than that?

If I do a fresh install, as ThemeGuru suggested, do I have to rebuild my website completely or are there certain files that can be uploaded that contain my customized files?

I resolved this issue. The error message was coming from the concrete/models folder. Upon comparing the upgrade to the files already on the server in that folder, there were several files that were not upgraded so I deleted them. The File Manager now appears.