Alpha Release: Xamarin 4, Cycle 6 – Service Release 0

BrendanZagaeskiBrendanZagaeski USForum Administrator, Xamarin Team Xamurai
edited December 2015 in General

This thread has now been closed to direct all further updates about this release onto the corresponding Stable release announcement:

Release Blog post:

This is a small bugfix release. It addresses a first handful of the more severe or commonly reported issues from the Xamarin 4, Cycle 6 Feature Release. See the Release Blog post for details.

Remaining known issues

An additional Service Release is tentatively planned for Alpha release within the next few weeks. It will include fixes for several other regressions introduced by the Cycle 6 Feature Release.

As mentioned on the Release Blog post, there is one especially widely reported regression for which a fix is not yet included in the Alpha version of Cycle 6 Service Release 0. This issue is under active investigation for a possible fix in a later build of Service Release 0:

  • [Xamarin.VS (36185)] – Hang (GUI lockup, freeze) when opening or working on a solution that contains an Android project. Known temporary workaround: delete the hidden .suo file or .vs folder in the solution directory.

Bug filing

If you find any new issues in this release compared to the current Stable versions or the previous "Xamarin 3" versions that you would like the Xamarin team to investigate, please do file a quick bug report, and then feel free to add a note on this thread with the bug number. Thanks!

New known issues

To save time be sure to check the lists of known issues in the release notes (linked below) before filing a bug.

You can view the complete list of new bug reports against the Xamarin 4 ("Cycle 6") Stable versions, excluding the issues fixed in Service Release 0 using the following Bugzilla query:

Previous versions, downgrading

You can install this new Alpha version or switch back to the current Stable version by changing updater channels.

Older versions

You can downgrade back to the previous Xamarin 3 Stable versions by manually reinstalling each old package. See the "Get the latest stable version of Xamarin 3" section on your account page: If you have any trouble downloading the previous versions from that link, would like to install an older set of versions, or simply would prefer an email with all the installer links you need, feel free to contact [email protected].

Release info



  • XamarinStudio- (bee8b40) (This is an update for Mac only) Release Notes
  • monotouch- (d070a7b) Release Notes

Release Blog post:

See the first entry in the release blog and "Xamarin Release Cycles" for more information about "cycles," "service releases," and "feature based releases."

Compatibility notes

(These are the same as for the initial Cycle 6 Feature Release.)

  • [XamarinVS] The Cycle 6 builds of XamarinVS now require Visual Studio 2012 or higher. Following along with the end of Mainstream Support for Visual Studio 2010 by Microsoft, Cycle 6 is not compatible with VS 2010.

  • [iOS] The Cycle 6 builds now require Xcode 7 or higher. For example, attempting to build an iOS app for device using Xcode 6.4 will now fail with "Native linking failed, undefined symbol: ___divdc3".

  • [Xamarin Studio] [XamarinVS] [iOS] [Android] [Xamarin.Mac] Support for OS X 10.9 Mavericks has been deprecated. The Cycle 6 builds now require OS X 10.10 Yosemite.

EDIT Nov 30: Make a small formatting change.


  • VictorHGarciaVictorHGarcia USUniversity ✭✭

    Excuse me @BrendanZagaeski , do you know if Xamarin support via email is in pause mode this week or somehow? I'm asking because I sent an email about an issue I'm having on monday (23th November, 2015) morning and not a reply yet.

    Thanks in advance

  • BrendanZagaeskiBrendanZagaeski USForum Administrator, Xamarin Team Xamurai
    edited November 2015

    Apologies for the slight delay. The volume of emails to the Support Team has been significantly higher this week (as is often the case after a large feature release like Xamarin 4). The Support Team has been tackling cases as quickly as possible. It looks like your email has just recently (about 1 hour ago) now received a first reply.

    As a side note in case it might be helpful, if you send any future support emails to one of the product-specific addresses listed on your account page ("Business & Enterprise Support"), you will receive an automatic confirmation once the Support Team receives the email.


  • Service release 0 seemed to fix all the issues I was having with locked files and build hangs. For several hours no problems. I switched build configs to release built and made an apk. After that and switching back to debug it was like I reverted to stable. Locked files, builds hanging, and even VS locking on startup mid while projects loaded.

  • softlionsoftlion FRBeta ✭✭✭

    Service release 0 does not fix any issue i have, and created a new issue where after a few hours it can not connect anymore to the mac, aven after a full reboot. I downgraded.

  • BrendanZagaeskiBrendanZagaeski USForum Administrator, Xamarin Team Xamurai
    edited December 2015

    locked files and build hangs

    Service Release 0 includes only 1 patch aimed at hangs or locked files (from the Release Blog post):

    36190 – Fixed an error "Could not write lines to file "obj\Debug\MyLib.csproj.FileListAbsolute.txt"" when building moderately large PCL projects as part of an iOS or Android app.

    Locked files other than *.csproj.FileListAbsolute.txt files would in theory not be affected by Service Release 0. (Note also that the patch for Bug 36190 simply changes the errors about those particular locked .txt files to warnings and allows the build to continue.)

  • BillBartlettBillBartlett USMember ✭✭

    Just filed new bug # 36405: "Xamarin.iOS 9.2 (Xam4) cannot produce 64 bit ActionExtensions". (It doesn't look like this has been filed yet. Used to work pre-Xamarin 4 update; works fine on my older, not-yet-updated machine...)

  • BrendanZagaeskiBrendanZagaeski USForum Administrator, Xamarin Team Xamurai

    This thread has now been closed to direct all further updates about this release onto the corresponding Stable release announcement:

This discussion has been closed.