Install gmountiso:
Start Synaptic Package Manager from Administration on top menu of ubuntu, type gmountiso in the Quich Search box. Right click on gmountiso and mark it to install. And then click Apply.
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Create a mount point:
In order to mount a ISO, you have to creat a mount point somewhere, just create a folder on your desktop is OK.
Start gmountiso from ubuntu top menu:
Applications > System Tools > Gmount-iso
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Just click Open to select Image File (.iso), and Mount Point, and then click the button mount.
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