Pierre, if your drive C is very full then installing WX5 on another drive may not resolve the problem (some files will always be installed/updated on the boot drive).

Can I suggest you first clean out unrequired files on yor drive C: before going down this path. Hopefully you will be surprised by how much space you can recover.

Into the search bar accessible from your task bar, type cleanup. Select Disk Clean-up app. When it appears also select clean up system files option. When ready place a tick in every group of files you wish to remove.

This is safe in that it is extremely unlikely you could ever delete a required file through this app.

Please advise if this helps.

If this does not release sufficient space then you can use software like "foldersize" to locate large or redundant files.

In my opinion if there is less than 10% free space on your boot drive, it is only a matter of time before your system will crash.

I vaguely remember that if you have had a previous installation you do not get to choose the installation drive. I suspect the incomedia folder needs removing from you appdata, local folder, but this will break any existing installations.

Please wait for a knowledgeable user to verify this before proceeding.

Thank you everybody for your comments.