(01:50:00) | Failed to call hook 'OnServerSave' on plugin 'BoxLooters v0.3.5' (NullReferenceException: Object reference not set to an instance of an object)
  at Oxide.Plugins.BoxLooters.SaveData () [0x00000] in <7e469a3c29014d3d858dc09f464d9f45>:0
  at Oxide.Plugins.BoxLooters.OnServerSave () [0x00000] in <7e469a3c29014d3d858dc09f464d9f45>:0
  at Oxide.Plugins.BoxLooters.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x00219] in <7e469a3c29014d3d858dc09f464d9f45>:0
  at Oxide.Plugins.CSharpPlugin.InvokeMethod (Oxide.Core.Plugins.HookMethod method, System.Object[] args) [0x00079] in <9affce1cd15c4ec183941adef8db1722>:0
  at Oxide.Core.Plugins.CSPlugin.OnCallHook (System.String name, System.Object[] args) [0x000d8] in <4452f821def6406d834e4149849fe7ea>:0
  at Oxide.Core.Plugins.Plugin.CallHook (System.String hook, System.Object[] args) [0x00060] in <4452f821def6406d834e4149849fe7ea>:0

This is most likely from your oxide/data for the plugin being corrupt and unreadable.

Fresh install and newest version, if currupt then its from the addon creating a currupt data file

Have you opened the file to see what it has in it? Extremely unlikely that it would create it corrupt, more likely something with your setup changed it.

18:52 [Error] Failed to call hook 'Unload' on plugin 'BoxLooters v0.3.5' (NullReferenceException: Object reference not set to an instance of an object)
  at Oxide.Plugins.BoxLooters.SaveData () [0x00000] in <9832dcbfaebf4c35ac47070891ad071f>:0 
  at Oxide.Plugins.BoxLooters.Unload () [0x00000] in <9832dcbfaebf4c35ac47070891ad071f>:0 
  at Oxide.Plugins.BoxLooters.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x002d0] in <9832dcbfaebf4c35ac47070891ad071f>:0 
  at Oxide.Plugins.CSharpPlugin.InvokeMethod (Oxide.Core.Plugins.HookMethod method, System.Object[] args) [0x00079] in <efb9a8684e344ecfa065c7b416e6d2fd>:0 
  at Oxide.Core.Plugins.CSPlugin.OnCallHook (System.String name, System.Object[] args) [0x000d8] in <b0a93b504f034a0db8b1c3d2503c0987>:0 
  at Oxide.Core.Plugins.Plugin.CallHook (System.String hook, System.Object[] args) [0x00060] in <b0a93b504f034a0db8b1c3d2503c0987>:0

using latest oxide version