Morrowind.ini cannot be written to

[tnash]

When I try to activate a mod, NMM comes up with an error message

 

BOSS_API_ERROR_FILE_WRITE_FAIL: "D:\The Elder Scrolls III- Morrowind\The Elder Scroll III\Morrowind.ini" cannot be written to!

Full Trace:

Nexus.Client.Games.Gamebryo.PluginManagement.Boss.BossException: BOSS_API_ERROR_FILE_WRITE_FAIL: "D:\The Elder Scrolls III- Morrowind\The Elder Scroll III\Morrowind.ini" cannot be written to!

at Nexus.Client.Games.Gamebryo.PluginManagement.Boss.BossSorter.HandleStatusCode(UInt32 p_uintStatusCode)

at Nexus.Client.Games.Gamebryo.PluginManagement.Boss.BossSorter.SetActivePlugins(String[] p_strActivePlugins)

at Nexus.Client.Games.Gamebryo.PluginManagement.InstallationLog.GamebryoActivePluginLogSerializer.SavePluginLog(IList`1 p_lstActivePlugins)

at Nexus.Client.PluginManagement.InstallationLog.ActivePluginLog.SavePluginLog()

at Nexus.Client.PluginManagement.InstallationLog.ActivePluginLog.TransactionEnlistment.Commit()

at Nexus.Client.PluginManagement.InstallationLog.ActivePluginLog.TransactionEnlistment.ActivatePlugin(Plugin p_plgPlugin)

at Nexus.Client.PluginManagement.InstallationLog.ActivePluginLog.ActivatePlugin(Plugin p_plgPlugin)

at Nexus.Client.PluginManagement.PluginManager.ActivatePlugin(Plugin p_plgPlugin)

at Nexus.Client.PluginManagement.UI.PluginManagerControl.rlvPlugins_ItemCheck(Object sender, ItemCheckEventArgs e)

at System.Windows.Forms.ListView.OnItemCheck(ItemCheckEventArgs ice)

at System.Windows.Forms.ListView.WmReflectNotify(Message& m)

at System.Windows.Forms.ListView.WndProc(Message& m)

at Nexus.Client.Controls.ReorderableListView.WndProc(Message& m)

at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)

at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)

at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)