Also, I cannot open up "Users And Groups" the page displayed is a Blank white page.

I've the same problem, is there a solution?

I haven't found any solution. I'm thinking of redoing my site. It's a personal site so it hasn't been that important to me. Sucks though I wanted to update it but can't.

Do you see anything in your web server logs? Have you tried clearing your browser and concrete5 caches?

I see this Logs. do you have a suggestion?
thanks for your help.

Exception Occurred: Invalid task permission.
#0 [internal function]: TaskPermission->__call('canInstallPacka...', Array)
#1 /srv/www/vhosts/grilledelephant.com/httpdocs/concrete/single_pages/dashboard/install.php(7): TaskPermission->canInstallPackages()
#2 /srv/www/vhosts/grilledelephant.com/httpdocs/concrete/libraries/view.php(752): include('/srv/www/vhosts...')
#3 /srv/www/vhosts/grilledelephant.com/httpdocs/concrete/dispatcher.php(246): View->render(Object(Page))
#4 /srv/www/vhosts/grilledelephant.com/httpdocs/index.php(2): require('/srv/www/vhosts...')
#5 {main}

I think I see a reference to "installPackage". Maybe there is an old, incompatible add-on package or custom block. Try removing all custom blocks and add-ons. then add them back in one at a time to figure out which one has the problem.

I removed all Blocks and hadnt any succeed. is it possible to delete the whole httpdocs folder and reinstall the concrete. To make a reference to the old database put all custom blocks in there folder and every thing works?without loosing any data?
The pictures and sites will still be there after reinstalling?

thanks for helping..

Yes, tried that still no go.

When going to Files on the Dashboard I get this:

File Manager

Fatal error: Cannot make static method AttributeKey::getList() non static in class FileAttributeKey in /home1/soltrekk/public_html/C5/concrete/models/file_attributes.php on line 241

When going to Users and Groups I get:
Fatal error: Cannot redeclare class UserAttributeKey in /home1/soltrekk/public_html/C5/concrete/models/user_attributes.php on line 326

When going to Add Functionality I get:
Fatal error: Cannot make static method AttributeKey::getList() non static in class CollectionAttributeKey in /home1/soltrekk/public_html/C5/concrete/models/collection_attributes.php on line 193