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After the download, navigate to System->System Information->Software Management.
Click on “Upload File” in the below screen to upload the downloaded RAR files (software, firmware, and license) and then click on Submit to finish the upload.
Note (Known Workaround - Fixed in version 6.3.5):
Please follow the below procedure if you are facing an issue upgrading MCM (fixed in version 6.3.5if running Microsoft Windows 11, because through a software update Microsoft changes they way windows handles .rar files).
Change the mime type of .RAR through Windows registry (see attached image):
Open Registry Editor
Expand the HKEY_CLASSES_ROOT section
Navigate to .RAR subsection and single click it. In the panel on the right double click the Content Type entry - editing dialog will open.
Edit the Value data field setting it to application/x-rar-compressed. On latest Windows versions .rar file are getting Application/x-compressed instead
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