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[SOLVED] Installing Qt 5.2 without wiping previous versions

  • I've been working with Qt 5.1.0 and maintaining code for Qt 4.8.3. Both versions live side by side in C:\Qt.

    I now ran the Windows (online) installer for Qt 5.2 and while offering the path C:\Qt as a default, the installer tells me :
    "You have selected an existing, non-empty folder for installation.
    Note that it will be completely wiped on uninstallation of this application.
    It is not advisable to install into this folder as installation might fail".

    What should I do? I don't want to start a different parent folder just for this Qt version but I also don't want to lose my previous versions. Am I misunderstanding the notification message?

  • I ended up installing to a separate parent folder but if anyone has input, I'd appreciate it.

  • Moderators


    I presume you installed Qt 5.1 through an offline installer?

    The online installer is designed to let you install multiple versions side-by-side, although it won't "adopt" your existing offline copy of Qt 5.1.

    When a new Qt version is released in the, run MaintenanceTool.exe (in the root of your online installation) to add the new version to your system.

    If you don't mind, you can uninstall your offline Qt 5.1 and re-install it through the online installer. Then you'll have all versions of Qt 5 managed through MaintenanceTool.exe.

  • JKSH, thanks for your reply. But the main issue for me is not to lose the Qt 4.8.3 version that I currently had installed in C:\Qt. That's why I ended up installing Qt 5.2 to a separate parent folder - with the web installer.

    Or would there be a way to not lose the older version?

  • Moderators

    You could move C:\Qt\4.8.3\ to a different folder temporarily, install the Qt 5 package manager into C:\Qt, and then move Qt 4.8.3 back. Then you'd have a structure like this:

    C:\Qt\4.8.3* <-- NOT managed by the package manager

    The package manager doesn't mind having "extra" folders in its root.

    P.S. Qt 4.8.5 is a bugfix release that is fully compatible with Qt 4.8.3 -- I'd recommend upgrading.

  • Thanks for that! I'll consider this configuration. As for Qt 4.8.5, most of the efforts are now put into the upgrade to Qt 5.2, so I guess the previous version will stay 4.8.3 for now.

  • Moderators

    You're welcome :) Happy coding!

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