i am getting the same problem. 

completely uninstalled, deleted both multiminer folders from within appdata, reinstalled, rebooted, re-installed latest drivers.
same message

See the end of this message for details on invoking
just-in-time (JIT) debugging instead of this dialog box.

************** Exception Text **************
Newtonsoft.Json.JsonReaderException: Unexpected character encountered while parsing value: Y. Path '', line 0, position 0.
   at Newtonsoft.Json.JsonTextReader.ParseValue()
   at Newtonsoft.Json.JsonTextReader.ReadInternal()
   at Newtonsoft.Json.JsonTextReader.Read()
   at Newtonsoft.Json.Linq.JArray.Load(JsonReader reader)
   at Newtonsoft.Json.Linq.JArray.Parse(String json)
   at MultiMiner.CoinChoose.Api.ApiContext.GetCoinInformation(String userAgent) in d:\Data\Visual Studio Projects\Personal\MultiMiner\MultiMiner.CoinChoose.Api\ApiContext.cs:line 33
   at MultiMiner.Win.MainForm.RefreshCoinStats() in d:\Data\Visual Studio Projects\Personal\MultiMiner\MultiMiner.Win\MainForm.cs:line 2458
   at MultiMiner.Win.MainForm.MainForm_Load(Object sender, EventArgs e) in d:\Data\Visual Studio Projects\Personal\MultiMiner\MultiMiner.Win\MainForm.cs:line 112
   at System.Windows.Forms.Form.OnLoad(EventArgs e)
   at System.Windows.Forms.Control.CreateControl(Boolean fIgnoreVisible)
   at System.Windows.Forms.Control.CreateControl()
   at System.Windows.Forms.Control.WmShowWindow(Message& m)
   at System.Windows.Forms.Control.WndProc(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
   at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)


************** Loaded Assemblies **************
mscorlib
    Assembly Version: 2.0.0.0
    Win32 Version: 2.0.50727.5472 (Win7SP1GDR.050727-5400)
    CodeBase: file:///C:/Windows/Microsoft.NET/Framework64/v2.0.50727/mscorlib.dll
----------------------------------------
MultiMiner.Win
    Assembly Version: 2.4.0.105
    Win32 Version: 2.4.0.105
    CodeBase: file[Suspicious link removed]
----------------------------------------
System.Drawing
    Assembly Version: 2.0.0.0
    Win32 Version: 2.0.50727.5467 (Win7SP1GDR.050727-5400)
    CodeBase: file:///C:/Windows/assembly/GAC_MSIL/System.Drawing/2.0.0.0__b03f5f7f11d50a3a/System.Drawing.dll
----------------------------------------
System
    Assembly Version: 2.0.0.0
    Win32 Version: 2.0.50727.5467 (Win7SP1GDR.050727-5400)
    CodeBase: file:///C:/Windows/assembly/GAC_MSIL/System/2.0.0.0__b77a5c561934e089/System.dll
----------------------------------------
System.Windows.Forms
    Assembly Version: 2.0.0.0
    Win32 Version: 2.0.50727.5468 (Win7SP1GDR.050727-5400)
    CodeBase: file:///C:/Windows/assembly/GAC_MSIL/System.Windows.Forms/2.0.0.0__b77a5c561934e089/System.Windows.Forms.dll
----------------------------------------
MultiMiner.Utility
    Assembly Version: 1.0.0.0
    Win32 Version: 1.0.0.0
    CodeBase: file:///C:/Users/administrator/AppData/Local/MultiMiner/MultiMiner.Utility.DLL
----------------------------------------
MultiMiner.CoinChoose.Api
    Assembly Version: 2.4.0.105
    Win32 Version: 2.4.0.105
    CodeBase: file:///C:/Users/administrator/AppData/Local/MultiMiner/MultiMiner.CoinChoose.Api.DLL
----------------------------------------
MultiMiner.Coin.Api
    Assembly Version: 2.4.0.105
    Win32 Version: 2.4.0.105
    CodeBase: file:///C:/Users/administrator/AppData/Local/MultiMiner/MultiMiner.Coin.Api.DLL
----------------------------------------
MultiMiner.Xgminer.Api
    Assembly Version: 2.4.0.105
    Win32 Version: 2.4.0.105
    CodeBase: file:///C:/Users/administrator/AppData/Local/MultiMiner/MultiMiner.Xgminer.Api.DLL
----------------------------------------
MultiMiner.Engine
    Assembly Version: 2.4.0.105
    Win32 Version: 2.4.0.105
    CodeBase: file:///C:/Users/administrator/AppData/Local/MultiMiner/MultiMiner.Engine.DLL
----------------------------------------
MultiMiner.Xgminer
    Assembly Version: 2.4.0.105
    Win32 Version: 2.4.0.105
    CodeBase: file:///C:/Users/administrator/AppData/Local/MultiMiner/MultiMiner.Xgminer.DLL
----------------------------------------
System.Xml
    Assembly Version: 2.0.0.0
    Win32 Version: 2.0.50727.5476 (Win7SP1GDR.050727-5400)
    CodeBase: file:///C:/Windows/assembly/GAC_MSIL/System.Xml/2.0.0.0__b77a5c561934e089/System.Xml.dll
----------------------------------------
System.Core
    Assembly Version: 3.5.0.0
    Win32 Version: 3.5.30729.5420 built by: Win7SP1
    CodeBase: file:///C:/Windows/assembly/GAC_MSIL/System.Core/3.5.0.0__b77a5c561934e089/System.Core.dll
----------------------------------------
Accessibility
    Assembly Version: 2.0.0.0
    Win32 Version: 2.0.50727.4927 (NetFXspW7.050727-4900)
    CodeBase: file:///C:/Windows/assembly/GAC_MSIL/Accessibility/2.0.0.0__b03f5f7f11d50a3a/Accessibility.dll
----------------------------------------
MultiMiner.CoinWarz.Api
    Assembly Version: 2.4.0.105
    Win32 Version: 2.4.0.105
    CodeBase: file:///C:/Users/administrator/AppData/Local/MultiMiner/MultiMiner.CoinWarz.Api.DLL
----------------------------------------
Newtonsoft.Json
    Assembly Version: 4.5.0.0
    Win32 Version: 5.0.8.16617
    CodeBase: file:///C:/Users/administrator/AppData/Local/MultiMiner/Newtonsoft.Json.DLL
----------------------------------------
System.Configuration
    Assembly Version: 2.0.0.0
    Win32 Version: 2.0.50727.5476 (Win7SP1GDR.050727-5400)
    CodeBase: file:///C:/Windows/assembly/GAC_MSIL/System.Configuration/2.0.0.0__b03f5f7f11d50a3a/System.Configuration.dll
----------------------------------------

************** JIT Debugging **************

hi,

there is definitely something not right about the pool shown.
coin is shown as tagcoin on one of my miners, pool as d2, accepted 84 shares

d2 don't have a tagcoin pool

I can see on the d2 pool for worldcoin that it is actually hashing there still

this time I manually switched pools

it wouldn't switch automatically despite tagcoin being more profitable on coinchoose and coinwarz and seems to have got stuck on worldcoin/d2 pool even with manual restarts

EDIT###
just did a full stop and start instead of a restart and the pool changed properly...

EDIT####
even with a manual change on a different pc it showed as pool of tagcoin (manually chosen) with a coin of digitalcoin until I disabled strategies and did stop & start

just a quick note to let you know that the new checkbox definitely fixes the r9 bsod issue for me
I installed on 3 setups and forgot to put on one and that one crashed after 5 minutes when I tried to restart
adding the checkbox and running fine with several restarts ever since
all my cards are r9 and running very efficiently now!

are there any posts I can reference re. the different profitability strategies?
it takes me probably at least 6-8hrs of constant mining to get a decent quantity of coins and mining rate
coins seem to almost deliberately adjust their difficulty so they become the most profitable for about 5 minutes then drop down
so looking for a combination of

stable exchange over the last week (green on the middle graph on coinwarz)
difficulty averaged over the last e.g. 24+ hrs (to avoid choosing a coin by accident that is most profitable for 5 mins - e.g. bottlecaps were shoing as earning a bitcoin in 1 day for about 5 minutes yesterday)
profitability relatively (i.e. in the top section on coinwarz)


profitability over the last week would seem to be the one, but presumably its _only_ backward looking?

thanks,

Dan

hi there,

really liking multiminer.  I just noticed that for some reason it shows the coin being mined correctly but seems to show the pool name as different (looks like the previously mined pool).

I was also wondering if you know if there is a recommended amount of time between switching with pplns pools (currently I set all miners to mine everything for 6hrs)

thanks,

Dan

Hi there,

a nxt donation would be greatly appreciated to go towards bringing down the time to forge from 4 yrs currently ;-)

I post on the original forum using the same username so I am a real person - honest!

thank you in advance

DLftGrZf8tjzDeMCRT4T9FbQ7ibG289iuA

thank you very much!

yes please

15124091752827015417

hi,

I have just set up my second p2pool litecoin server.  The first has about 8 machines cpumining.
I added a graphics card to it and it stopped paying out.
i fixed the problems hardware errors etc and set it going very slowly (r9 290 at about 430mh, zero hw errors and <1% doa)
still no payouts after over 24 hrs

created a new p2pool server running Ubuntu and its been running for over 24hrs with no payout or efficiency showing still

if i restart the old server it picks up a share in about 6-8hrs and starts paying relatively quickly. 
if i restart the new one (or use the jinxed machine anywhere) it never works
i have tried using cgminer, bfgminer, and currently guiminer scrypt
the server seems to be connected and has both incoming and outgoing connections
server is http://mining.pirantech.co.uk:9327/static/

does anyone have any ideas about where i might be going wrong?

thanks in advance