I am getting the following error when trying to attach a file either from local or server to an item in K2:
Fatal error: Call to undefined method JUtility::getHash() in C:\xampp\htdocs\joomla301\administrator\components\com_k2\models\item.php on line 997

There is no issue if I do not attach a file to the item. Everything else woks perfectly.

Please help!

Issue occurs in both front-end and administrator for items with attachments. Error produced = "Call to undefined method getHash()".

Solution current code base calls JUtility::getHash(); which was changed to JApplication::getHash in the recent update to the Joomla Framework in Joomla 3.0.1

call to getHash() exists in the following locations. In my test fix, I just changed the call, however at version test should be performed as Joomla 2.5 still uses the JUtility;;getHash() call.

Front End Line 1333 of /components/com_k2/models/item.php

Administrator Lines 937 and 997 of /administrator/components/com_k2/models/item.php

You can make this adjustment yourself for now, I've also just posted this bug on Issues page.

This issue has already been fixed in the SVN. Thanks for reporting.

Thanks for the good news.

Any idea when will you be releasing K2 2.6.2?

I'm having the same problem. Running a new Rockettheme Metropolis J3.0.2.

After I installed K2 2.6.1 I can no longer get to the template config.

An error has occurred.

500 View not found [name, type, prefix]: gantry, html, gantryView

I found that unactive k2 system plugin make gantry work again.

I have same problem :(

Anyone facing this issue, please update to K2 2.6.2 and provide some feedback.

I have the newest gantry template installed and k2 2.6.2 and having this same issue when I try to access the template from the backend:

An error has occurred.

500 View not found [name, type, prefix]: gantry, html, gantryView

I want to use K2 on this site but I have to access the gantry template. Any ideas on how to fix this?

Is there any update on how to fix this issue?

Same issue here.
Using Gantry framework, and Cerulean Rockettheme template with Joomla 3.0.4 & K2 2.6.2

As soon as K2 was uninstalled, I had access to the template again.

I have the same problem. Joomla 3.0.2. K2 2.6.2, Rocket Theme Cerulean template 1.0, Gantry 4.1.4

If I unpublish the System - K2 plugin I can then access the template from the backend.

When you look at k2.php (the system plugin) you can see that the K2 devs are using

JRequest::getCmd()

which is deprecated.

They should use

JFactory::getApplication()->input->get() instead.

docs.joomla.org/Potential_backward_compatibility_issues_in_Joomla_3.0_and_Joomla_Platform_12.1

Workaround: Just select template name with checkbox and click on Edit button. That will do the same as if you clicked on template name ...

Perhaps "one day" the K2 guys will change that (and stop blaming Gantry) ...

I guess you could also just "search & replace"
JRequest::getCmd with Factory::getApplication()->input->get
in the k2.php ... but I haven't tested that.