Can't install extension?

New to slicer, tried to install registration but failed

For both Slicer versions 5.0.3 and 5.1.0

You may need to click Check for updates button to force downloading latest extension descriptions file from the server and then click Install. (This issue was fixed in the very latest Slicer-5.1 releases)

Checked but problem still

Have you clicked Check for updates and then Install for the extension? Can you install some extensions just not Elastix?

Yes I clicked Check for updates as shown in the screenshot above, and then Install for the extension.

I tried to install Airway Segmentation and DCMQi but none of them works

Are you behind some corporate or hospital firewall or proxy server?

If you click the Open extension catalog website button can you download extensions from there?

Can you find any additional information about the failed download in the application log (no write access in temporary folder, out of disk space, etc)?

Yes I’m behind my hospital’s firewall and yes when I clicked the Open extension catalog website button I can download extensions from there.

Where to find the application log? Truely thank you!

You can find the application log in menu: Help / Report a bug. Please check if you find any additional information.

Hospital firewalls might interfere communication between the extension frontend and backend. Could you try installing the extension via bookmarks:

  • click on the wrench icon (in the Extensions Manager in the top-right corner)
  • select Edit bookmarks
  • type SlicerElastix to the textbox, click OK
  • click Install bookmarked button (near the top)

Information from the log file:

====================================================================
[DEBUG][Qt] 22.09.2022 12:07:53 [] (unknown:0) - Session start time .......: 2022-09-22 12:07:53
[DEBUG][Qt] 22.09.2022 12:07:53 [] (unknown:0) - Slicer version ...........: 5.1.0-2022-09-19 (revision 31142 / cc3ca58) win-amd64 - installed release
[DEBUG][Qt] 22.09.2022 12:07:53 [] (unknown:0) - Operating system .........: Windows /  Professional / (Build 19042, Code Page 65001) - 64-bit
[DEBUG][Qt] 22.09.2022 12:07:53 [] (unknown:0) - Memory ...................: 130805 MB physical, 150261 MB virtual
[DEBUG][Qt] 22.09.2022 12:07:53 [] (unknown:0) - CPU ......................: GenuineIntel , 16 cores, 16 logical processors
[DEBUG][Qt] 22.09.2022 12:07:53 [] (unknown:0) - VTK configuration ........: OpenGL2 rendering, TBB threading
[DEBUG][Qt] 22.09.2022 12:07:53 [] (unknown:0) - Qt configuration .........: version 5.15.2, with SSL, requested OpenGL 3.2 (compatibility profile)
[DEBUG][Qt] 22.09.2022 12:07:53 [] (unknown:0) - Internationalization .....: disabled, language=
[DEBUG][Qt] 22.09.2022 12:07:53 [] (unknown:0) - Developer mode ...........: disabled
[DEBUG][Qt] 22.09.2022 12:07:53 [] (unknown:0) - Application path .........: C:/Users/4472950/AppData/Local/NA-MIC/Slicer 5.1.0-2022-09-19/bin
[DEBUG][Qt] 22.09.2022 12:07:53 [] (unknown:0) - Additional module paths ..: (none)
[DEBUG][Python] 22.09.2022 12:08:04 [Python] (C:\Users\4472950\AppData\Local\NA-MIC\Slicer 5.1.0-2022-09-19\lib\Slicer-5.1\qt-scripted-modules\SubjectHierarchyPlugins\AbstractScriptedSubjectHierarchyPlugin.py:38) - Scripted subject hierarchy plugin registered: Annotations
[DEBUG][Python] 22.09.2022 12:08:05 [Python] (C:\Users\4472950\AppData\Local\NA-MIC\Slicer 5.1.0-2022-09-19\lib\Slicer-5.1\qt-scripted-modules\SubjectHierarchyPlugins\AbstractScriptedSubjectHierarchyPlugin.py:38) - Scripted subject hierarchy plugin registered: SegmentEditor
[DEBUG][Python] 22.09.2022 12:08:05 [Python] (C:\Users\4472950\AppData\Local\NA-MIC\Slicer 5.1.0-2022-09-19\lib\Slicer-5.1\qt-scripted-modules\SubjectHierarchyPlugins\AbstractScriptedSubjectHierarchyPlugin.py:38) - Scripted subject hierarchy plugin registered: SegmentStatistics
[DEBUG][Qt] 22.09.2022 12:08:05 [] (unknown:0) - Switch to module:  "Welcome"
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/b/bc/BaselineFollowupSCANRegisteredCMFreg2.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://wiki.slicer.org/slicerWiki/images/2/2a/CarreraSliceEffect.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/b/b9/ChangeTracker_logo.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/b/b7/CurveMakerIcon.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://slicer.org/slicerWiki/images/9/92/DSC_logo_Resized.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/a/ac/ErodeDilateLabelIcon.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/1/16/FilmDosimetry_Logo_128x128.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/f/f1/GelDosimetry_Logo_128x128.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/a/a7/GyroGuide.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/e/e5/QuickToolsLogo.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://wiki.slicer.org/slicerWiki/images/f/f6/IntensitySegmenterIcon.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/e/e8/MatlabBridgeLogo.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://slicer.org/slicerWiki/images/4/43/Slicer4ExtensionModelToModelDistance.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/a/ac/PAAlogo-small.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/2/21/PerkTutorLogo.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/b/b1/DPetBrainQuantification.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://wiki.slicer.org/slicerWiki/images/3/34/PkModeling.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/a/a7/Portplacement_icon.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://wiki.slicer.org/slicerWiki/images/d/d6/ResectionPlannerLogo.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://www.na-mic.org/Wiki/images/a/ad/Spharm-pdm-icon.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/b/ba/SegAidedRegSquareFocus128.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/f/f2/SkullStripper.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://raw.githubusercontent.com/SlicerDMRI/slicerdmri.github.io/master/images/DMRI_3D_SLICER-icon.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://raw.githubusercontent.com/QIICR/SlicerDevelopmentToolbox/master/Resources/Icons/SlicerDevelopmentToolbox.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/2/2b/SlicerIGTLogo.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/f/ff/SlicerLiver.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://wiki.slicer.org/slicerWiki/images/8/87/SlicerProstate_Logo_1.0_128x128.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/2/29/SlicerRT_Logo_3.0_128x128.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/6/64/SlicerToKiwiExporterLogo.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://slicer.org/slicerWiki/images/3/32/T1_Mapping_Logo_Resized.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://wiki.slicer.org/slicerWiki/images/9/92/TCIABrowser_logo.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:58 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/c/c2/VolumeClipLogo.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 12:13:59 [] (unknown:0) - A cookie associated with a cross-site resource at http://www.nitrc.org/ was set without the `SameSite` attribute. A future release of Chrome will only deliver cookies with cross-site requests if they are set with `SameSite=None` and `Secure`. You can review cookies in developer tools under Application>Storage>Cookies and see more details at https://www.chromestatus.com/feature/5088147346030592 and https://www.chromestatus.com/feature/5633521622188032.
[DEBUG][Qt] 22.09.2022 12:14:08 [] (unknown:0) - Retrieving extension metadata for AirwaySegmentation extension
[DEBUG][Qt] 22.09.2022 12:14:08 [] (unknown:0) - Retrieving AirwaySegmentation extension files (extensionId: 632969c4e911182f1dfca50c)
[DEBUG][Qt] 22.09.2022 12:14:08 [] (unknown:0) - Downloading AirwaySegmentation extension (item_id: 632969c4e911182f1dfca50c, file_id: 632969c5e911182f1dfca514)
[CRITICAL][Qt] 22.09.2022 12:14:08 [] (unknown:0) - Failed downloading: https://slicer-packages.kitware.com/api/v1/file/632969c5e911182f1dfca514/download
[WARNING][Qt] 22.09.2022 13:15:24 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win?q=log' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/b/b9/ChangeTracker_logo.png'. This content should also be served over HTTPS.
[WARNING][Qt] 22.09.2022 13:15:24 [] (unknown:0) - Mixed Content: The page at 'https://extensions.slicer.org/catalog/All/31142/win?q=log' was loaded over HTTPS, but requested an insecure image 'http://www.slicer.org/slicerWiki/images/a/ac/ErodeDilateLabelIcon.png'. This content should also be served over HTTPS.
[DEBUG][Qt] 22.09.2022 13:15:37 [] (unknown:0) - Retrieving extension metadata for VASSTAlgorithms extension
[DEBUG][Qt] 22.09.2022 13:15:37 [] (unknown:0) - Retrieving VASSTAlgorithms extension files (extensionId: 632988dae911182f1dfcc9d4)
[DEBUG][Qt] 22.09.2022 13:15:37 [] (unknown:0) - Downloading VASSTAlgorithms extension (item_id: 632988dae911182f1dfcc9d4, file_id: 632988dbe911182f1dfcc9db)
[CRITICAL][Qt] 22.09.2022 13:15:37 [] (unknown:0) - Failed downloading: https://slicer-packages.kitware.com/api/v1/file/632988dbe911182f1dfcc9db/download

Thank you, the messages indicates that Slicer downloads from the correct location but the download server returns an error, which is most likely due to a too strict proxy server.

If downloading via bookmarking does not work then you can download the extension packages using the Extensions Catalog website and then install the packages using Install from file.