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Error MT2001

Hi there,

i'm getting this error:

Error MT2001: Could not link assemblies. Reason: Argument is out of range. (MT2001)

Can you help me?



  • I forgot, it happens only when trying debug to the device

  • JeffreyVoorhaarJeffreyVoorhaar NLMember

    Having the same issue since I updated to the latest stable version this morning. It happens both in Debug and Release builds for iPhone; the simulator works fine.

    This is a more detailed error:

    Compiling to native code
    /Developer/MonoTouch/usr/bin/mtouch -sdkroot "/Applications/" --cache "/Users/jeffreyvoorhaar/Projects/Applications/Mobile/CashRegister/Cashr 1.0/Rlz.Mobile.CashRegister.iOS/obj/iPhone/Debug/mtouch-cache" --nomanifest --nosign -dev "/Users/jeffreyvoorhaar/Projects/Applications/Mobile/CashRegister/Cashr 1.0/Rlz.Mobile.CashRegister.iOS/bin/iPhone/Debug/" -r "/Users/jeffreyvoorhaar/Projects/Applications/Mobile/Common/Release 1.1.0 (77a)/Rlz.Mobile.Common/bin/iPhone/Debug/Rlz.Mobile.Common.iOS.dll" -r "/Users/jeffreyvoorhaar/Projects/Core/80a Working/Rlz.DTO/bin/iPhone/Debug/Rlz.Mobile.DTO.iOS.dll" -r "/Users/jeffreyvoorhaar/Projects/Core/80a Working/Rlz/bin/iPhone/Debug/Rlz.Mobile.iOS.dll" -r "/Users/jeffreyvoorhaar/Projects/Applications/Mobile/CashRegister/Cashr 1.0/Rlz.Mobile.CashRegister.Common/bin/iPhone/Debug/Rlz.Mobile.CashRegister.Common.iOS.dll" -r "/Developer/MonoTouch/usr/lib/mono/2.1/System.dll" -r "/Developer/MonoTouch/usr/lib/mono/2.1/System.Xml.dll" -r "/Developer/MonoTouch/usr/lib/mono/2.1/System.Core.dll" -r "/Developer/MonoTouch/usr/lib/mono/2.1/System.Data.dll" -r "/Developer/MonoTouch/usr/lib/mono/2.1/monotouch.dll" -r "/Developer/MonoTouch/usr/lib/mono/2.1/Mono.Data.Sqlite.dll" -debug -linksdkonly -sdk "6.1" -targetver "3.1" --abi=armv7 "-aot" "nimt-trampolines=512" "-aot" "ntrampolines=2048" "/Users/jeffreyvoorhaar/Projects/Applications/Mobile/CashRegister/Cashr 1.0/Rlz.Mobile.CashRegister.iOS/bin/iPhone/Debug/RlzMobileCashRegisteriOS.exe"
    MonoTouch Business version 6.4.0 using framework: /Applications/
    error MT2001: Could not link assemblies. Reason: Argument is out of range.
    Parameter name: indexB

    Here is my version information:

    === Xamarin Studio ===

    Version 4.0.10 (build 7)
    Installation UUID: 9b616b4a-b49d-46b5-b162-b66b3ef757ca
    Mono 3.2.0 ((no/7c7fcc7)
    GTK 2.24.20
    GTK# (
    Package version: 302000000

    === Apple Developer Tools ===

    Xcode 4.6.3 (2068)
    Build 4H1503

    === Xamarin.iOS ===

    Version: (Business Edition)
    Hash: c9f7659
    Build date: 2013-18-07 21:36:03-0400

    === Xamarin.Android ===

    Not Installed

    === Xamarin.Mac ===

    Xamarin.Mac: Not Installed

    === Build Information ===

    Release ID: 400100007
    Git revision: f324e2154ee86ae1b6b8483392eddbf418e6381b
    Build date: 2013-07-20 06:23:58+0000
    Xamarin addins: fe4f180e2386eafc00087ef68c3a580cff4a2592

    === Operating System ===

    Mac OS X 10.8.4
    Darwin MACJVO 12.4.0 Darwin Kernel Version 12.4.0
    Wed May 1 17:57:12 PDT 2013
    root:xnu-2050.24.15~1/RELEASE_X86_64 x86_64

    I made a big mistake in updating this morning, as I have to get a new version out today and I can't make any device builds now.

    Any suggestions?

  • Any help? can i downgrade de version?

  • moljacmoljac HRBeta ✭✭✭
    1. XS
    2. Check for updates
    3. Update Channel = stable | beta ( is alpha)
  • JeffreyVoorhaarJeffreyVoorhaar NLMember was obtained from the stable channel, in fact. I have always only subscribed to the stable channel and only switched to beta yesterday to see if a fix for my issues was available.

    Just received the following email response from Xamarin:

    "The MT2001 error you are running into will be resolved in Xamarin.iOS 6.4.1. The fix should be released on our Beta channel today."

    Just checked, there is indeed a 6.4.1 in the beta channel now with release notes forthcoming. I just installed it and it seems to work fine again!

    I also had simulator issues (very unstable threading) after updating yesterday. In the same mail, Xamarin said they were looking into that as well right now.

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