Cannot save civivolunteer project
I had the same issue. After enabling debugging I saw that the civicrm_volunteer_project table was missing the title field.

There is an alter query in this file that did not run correctly for me as it failed on removing the foreign key.

extensions/org.civicrm.volunteer/sql/volunteer_upgrade_2.0.sql

Modified version (though you should run your own tests):


ALTER TABLEcivicrm_volunteer_project
ADDtitleVARCHAR(255) COLLATE utf8_unicode_ci NOT NULL
  COMMENT 'The title of the Volunteer Project'
  AFTERid,
ADDdescriptionTEXT COLLATE utf8_unicode_ci
  COMMENT 'Full description of the Volunteer Project. Text and HTML allowed. Displayed on sign-up screens.'
  AFTERtitle,
ADDloc_block_idINT(10) unsigned DEFAULT NULL
  COMMENT 'FK to Location Block ID'
  AFTERis_active,
ADD CONSTRAINTFK_civicrm_volunteer_project_loc_block_id
  FOREIGN KEY (loc_block_id)
  REFERENCEScivicrm_loc_block(id)
  ON DELETE SET NULL,
ADDcampaign_idINT(10) unsigned DEFAULT NULL
  COMMENT 'The campaign associated with this Volunteer Project.'
  AFTERloc_block_id,
ADD CONSTRAINTFK_civicrm_volunteer_project_campaign_id
  FOREIGN KEY (campaign_id)
  REFERENCEScivicrm_campaign(id)
  ON DELETE SET NULL,
MODIFYentity_tablevarchar(64) NULL,
MODIFYentity_idint(10) NULL;