Running two servers with very similiar setups. The only plugins in any way managing inventory is SortingButton and QuickSort. For some reason it works just fine on one server but not the other. It will not even load the plugins on the server having trouble. These are the only two mods not working - other's like BetterChat etc works without trouble. Any reason this could be happening? 

Can you clarify what you mean by the plugin doesn't load? Do you see an error when trying to load the plugin?

Hello again. Sorry for not being clear in my first post. So this is what I get after running o.reload SortButton in the console.

(11:13:27) | SortButton was compiled successfully in 2227ms
(11:13:27) | Unloaded plugin Sort Button v2.0.2 by MON@H
(11:13:27) | Could not initialize plugin 'SortButton v2.0.2' (JsonReaderException: Unexpected character encountered while parsing value: [. Path '['Chat command']', line 9, position 19.)
at Newtonsoft.Json.JsonTextReader.ReadStringValue (Newtonsoft.Json.ReadType readType) [0x00366] in <271c58b7a8684db5a2c92be17a81f252>:0
at Newtonsoft.Json.JsonTextReader.ReadAsString () [0x00000] in <271c58b7a8684db5a2c92be17a81f252>:0
at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.ReadForType (Newtonsoft.Json.JsonReader reader, Newtonsoft.Json.Serialization.JsonContract contract, System.Boolean hasConverter) [0x00077] in <271c58b7a8684db5a2c92be17a81f252>:0
at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.PopulateDictionary (System.Collections.IDictionary dictionary, Newtonsoft.Json.JsonReader reader, Newtonsoft.Json.Serialization.JsonDictionaryContract contract, Newtonsoft.Json.Serialization.JsonProperty containerProperty, System.String id) [0x00262] in <271c58b7a8684db5a2c92be17a81f252>:0
at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateObject (Newtonsoft.Json.JsonReader reader, System.Type objectType, Newtonsoft.Json.Serialization.JsonContract contract, Newtonsoft.Json.Serialization.JsonProperty member, Newtonsoft.Json.Serialization.JsonContainerContract containerContract, Newtonsoft.Json.Serialization.JsonProperty containerMember, System.Object existingValue) [0x002a8] in <271c58b7a8684db5a2c92be17a81f252>:0
at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.CreateValueInternal (Newtonsoft.Json.JsonReader reader, System.Type objectType, Newtonsoft.Json.Serialization.JsonContract contract, Newtonsoft.Json.Serialization.JsonProperty member, Newtonsoft.Json.Serialization.JsonContainerContract containerContract, Newtonsoft.Json.Serialization.JsonProperty containerMember, System.Object existingValue) [0x0006d] in <271c58b7a8684db5a2c92be17a81f252>:0
at Newtonsoft.Json.Serialization.JsonSerializerInternalReader.Deserialize (Newtonsoft.Json.JsonReader reader, System.Type objectType, System.Boolean checkAdditionalContent) [0x000d9] in <271c58b7a8684db5a2c92be17a81f252>:0
at Newtonsoft.Json.JsonSerializer.DeserializeInternal (Newtonsoft.Json.JsonReader reader, System.Type objectType) [0x00053] in <271c58b7a8684db5a2c92be17a81f252>:0
at Newtonsoft.Json.JsonSerializer.Deserialize (Newtonsoft.Json.JsonReader reader, System.Type objectType) [0x00000] in <271c58b7a8684db5a2c92be17a81f252>:0
at Newtonsoft.Json.JsonConvert.DeserializeObject (System.String value, System.Type type, Newtonsoft.Json.JsonSerializerSettings settings) [0x0002d] in <271c58b7a8684db5a2c92be17a81f252>:0
at Newtonsoft.Json.JsonConvert.DeserializeObject[T] (System.String value, Newtonsoft.Json.JsonSerializerSettings settings) [0x00000] in <271c58b7a8684db5a2c92be17a81f252>:0
at Newtonsoft.Json.JsonConvert.DeserializeObject[T] (System.String value) [0x00000] in <271c58b7a8684db5a2c92be17a81f252>:0
at Oxide.Core.Libraries.Lang.GetMessageFile (System.String plugin, System.String lang) [0x00067] in <157a94ee66ab4a7991faecd1eb84be3b>:0
at Oxide.Core.Libraries.Lang.RegisterMessages (System.Collections.Generic.Dictionary`2[TKey,TValue] messages, Oxide.Core.Plugins.Plugin plugin, System.String lang) [0x00032] in <157a94ee66ab4a7991faecd1eb84be3b>:0
at Oxide.Plugins.SortButton.LoadDefaultMessages () [0x000ac] in <7ff0e1195ca4482f9df8b344b48c38bd>:0
at Oxide.Core.Plugins.Plugin.HandleAddedToManager (Oxide.Core.Plugins.PluginManager manager) [0x0001d] in <157a94ee66ab4a7991faecd1eb84be3b>:0
at Oxide.Core.Plugins.CSPlugin.HandleAddedToManager (Oxide.Core.Plugins.PluginManager manager) [0x00000] in <157a94ee66ab4a7991faecd1eb84be3b>:0
at Oxide.Plugins.CSharpPlugin.HandleAddedToManager (Oxide.Core.Plugins.PluginManager manager) [0x00000] in <23ba99f131254889867c71f0bd137b1d>:0
at Oxide.Plugins.CovalencePlugin.HandleAddedToManager (Oxide.Core.Plugins.PluginManager manager) [0x000b3] in <23ba99f131254889867c71f0bd137b1d>:0
at Oxide.Core.Plugins.PluginManager.AddPlugin (Oxide.Core.Plugins.Plugin plugin) [0x00027] in <157a94ee66ab4a7991faecd1eb84be3b>:0
at Oxide.Core.OxideMod.PluginLoaded (Oxide.Core.Plugins.Plugin plugin) [0x00035] in <157a94ee66ab4a7991faecd1eb84be3b>:0
(11:13:27) | No previous version to rollback plugin: SortButton

That says your config file has invalid json syntax.

I deleted the config and lang files and that seems to have done the trick. Thank you. It has been running without issue since last year in July or so, current version. Stopped working out of nowhere and only on one of the servers.