I am running K2 (Version 2.7.1) on a local instance of WAMP running Joomla 3.6.2. I was able to edit K2 items perfectly, but suddenly this morning, when trying to go into K2 (just the items) I'm being shown the following error (reporting is set to maximum):

Fatal error: Allowed memory size of 268435456 bytes exhausted (tried to allocate 17312936 bytes) in C:\wamp\www\client_sites\sitenameremoved\libraries\joomla\application\web.php on line 763
Call Stack

# Time Memory Function Location
1 0.0076 262024 {main}( ) ..\index.php:0
2 0.7044 5922712 JApplicationCms->execute( ) ..\index.php:51
3 97.6680 227415512 JApplicationAdministrator->render( ) ..\cms.php:263
4 97.6686 227416432 JApplicationCms->render( ) ..\administrator.php:433
5 98.4181 263286216 JApplicationBase->triggerEvent( ) ..\cms.php:1068
6 98.4182 263286264 JEventDispatcher->trigger( ) ..\base.php:106
7 98.4246 263339360 JEvent->update( ) ..\dispatcher.php:159
8 98.4246 263339816 call_user_func_array:{C:\wamp\www\client_sites\sitenameremoved\libraries\joomla\event\event.php:69} ( ) ..\event.php:69
9 98.4247 263339944 PlgSystemAdvancedModules->onAfterRender( ) ..\event.php:69
10 98.4247 263340184 PlgSystemAdvancedModulesHelper->replaceLinks( ) ..\advancedmodules.php:89
11 98.4249 263340320 JApplicationWeb->getBody( ) ..\helper.php:117
12 98.4249 263340704 implode ( ) ..\web.php:763

I have rebooted WAMP and the PC it's running on, but can't work out what's changed. This error has only just started showing.

It's a memory limit error coming from Joomla! core files.
You need to increase WAMP's memory limits.

Thanks, I'll do that now!

You 're welcome Russell :)