What did you do to fix permissions? Did you fix the permission for all destination folders specified by this 3D extension so you can create file in those folders?
Could you provide the link for this 3D "Materials" extensions (materials.zxp)? I can try it to figure out this extension would install what files into what directories. Then maybe you could check those files/directories one by one to make sure you can install the file into the directory.
This extension would install some files into <Photoshop CS5 installation folder>/Presets/Materials folder. Could you check whether you have permission to create file under that folder?
I think you can check it by:
1. Go to Photoshop CS5 installation folder. Default it should be /Applications/Adobe Photoshop CS5.
2. Go to sub folder Presets->Materials.
3. Try to create a new file under this folder. (Copying a file to this folder will do)
If you can't create a new file under this folder, you need to change the permission of this folder. Then try to install the extension again.
I was able to get mine to install once i gave permissions to
C:\Program Files\Adobe\Adobe Photoshop(64 Bit)
It told me it was trying to install the Materials.mxi to that folder.
Thanks. I've had the same problem. Changing the permissions on this folder worked for me.
I have this same problem with Extension Manager 2.1.115 (latest version for CS4). I am running as an administrator, have tried repairing permissions, have alsotried enabling root, and none of these things have not fixed the problem, which implies that there is a fundamental problem with the Extensions Manager.
Here's why this is totally pathetic:
1. The error message doesn't give you any clue about which folder it is trying to access which means that you have no idea what to do to fix it. The application must know which folder caused the problem so it could tell you in the error dialog.
2. The application (Extension Manager) should be able to escalate permissions as necessary to complete its task - other installers can do it fine, why can't this app?
3. The permissions for all the Adobe apps have been set by the Adobe installer when the applications were installed, so if there is a problem it must have been created by the Adobe installer.
4. Someone at Adobe must be aware of this issue and they obviously haven't attempted to fix it.
This is just SO typical of Adobe. This is either a result of very lazy (or incompetent) programming or is deliberately obstructive - I can't come up with any other explanation. I do sometimes wonder if there aren't people at Adobe who simply hate their customers and so come up with things like this to frustrate them. They don't deserve to be successful and it is no wonder that most people hate them as a supplier and would love to have an alternative to their products.
Sadly, I just found this, and it is still a problem.