[vfowler]

I resolved my problem with the error of `Call to undefined function bp_displayed_user_id() in C:xampphtdocsbpwp-contentpluginsbuddypressbp-corebp-core-template.php on line 1117` by:
1. reverting to the old 1.5.7 version of BuddyPress plugin
2. deactivating BuddyPress plugin – silly me for not doing this the first time
3. deactivating a BuddyPress dependent plugin ( User Name Availability Checker for wordpress/buddypress from http://buddydev.com/buddypress/creating-a-buddypress-wordpress-username-availability-checker-for-your-site )
4. then updating BuddyPress
5. and finally reactivating BuddyPress and dependent plugins
The moral of this story: I should always deactivate significant plugins such as BuddyPress before updating. All good now

[vfowler]

Call to undefined function bp_displayed_user_id() in C:xampphtdocsbpwp-contentpluginsbuddypressbp-corebp-core-template.php on line 1117

Above is the error I received after updating my test server. I too may have to hold off on updating…