Same problem here. The K2 Upgrade kept failing so I manually downloaded 2.6 and installed it. Now I'm getting this same error message.

I have the same problem. Unfortunately before understanding that was a k2 problem I have update two of my domains!
:(
No solutions I see
:(

hi
i have the same problem here,after i upgraded from v2.5.7 to v2.6 from joomla panel i got the same error :

Model class cpanelModelCpanel not found in file
even worse is that Mini K2 module gives error too:
Please check your setting to get the items or maybe you need to write your K2 items first
does installing v2.5.7 solve the problem?
unfortunately i don't have the v2.5.7,where can i download it?
and i wonder to know if installing previous version delete the existing data in database?!
oooooh god why did i do the upgrade!!! :(
i hope someone finds a solution!

Workaround reinstall the previous version, I leave a link to download it, I'll leave a few days until they fix the new version (remember to backup your database):

www.box.com/s/fgbjd2maqm6468k7nv3g

File no longer available for download

thanks dude!

Does any of the admin (or developer of the extension) aware of this error?

Anyone having the " Model class cpanelModelCpanel not found in file " error under K2 2.6 just remove the file /administrator/components/com_k2/models/cpanel.php.

@Михаил Новак

What version of Joomla! are you using? K2 2.6 only supports Joomla! 1.5, 2.5 and 3.0.

Hi Everyone,

Anyone having the " Model class cpanelModelCpanel not found in file " error under K2 2.6 just remove the file /administrator/components/com_k2/models/cpanel.php.

I followed this instruction and the problem was solved, however, I have one question, might this not affect any of default K2 features?

Yes, it does work since I remove the file. But I have the same concern with Tomy Francois, does this effect the whole K2 system? If doesn't effect, why does it exist? Can the developer totally remove from the K2 package so that no one will see that error message again?

Tomy Francois wrote: Hi Everyone,

Anyone having the " Model class cpanelModelCpanel not found in file " error under K2 2.6 just remove the file /administrator/components/com_k2/models/cpanel.php.

I followed this instruction and the problem was solved, however, I have one question, might this not affect any of default K2 features?