i think it is because the palette isn't fixed in position. you have it floating around so when you minimise the window it automatically disappears. I had this problem, i just grabbed the palette by the top bar and moved it over the channels palette (the bar has to be on top of the channels bar) and then it snatched into place
Prior to CS4, panels were referred to as palettes. A panel or palette is a box (usually located on the right hand side of the screen, but moveable) that allows you to change options associated with a Photoshop feature. For example, the layers panel or palette is used to manipulate layers; the character panel or palette is used to manipulate text.
Select layer You want to transform (click on it at LAYERS palette) then press Ctrl + T.
You can save thumbnail preview with image in Save or Save As dialog. Thumbnails in LAYERS palette you can choose thumbnail options from LAYERS panel options (top right corner of LAYERS palette > Panel Options).
Select that layer (click on it on LAYERS palette) where is something You want to add glow effect then click on fx at bottom of LAYERS palette and choose Outer glow effect (or Inner).
Use Transparency slider in LAYERS palette.
Using blend modes. Blend modes U can access from top of LAYERS palette for example
If the Layers palette is missing, you can return it by clicking on the "Window" menu near the top of Photoshop, then selecting "Layers" to ad a checkmark next to it, indicating that it is now visible. Photoshop also allows palettes to be un-docked from the program and dragged around anywhere on your screen, not just in the Photoshop window, so if you have a dual-monitor setup, make sure that you didn't somehow hide the palette on your second monitor.
To unlock layer press padlock icon on top of layers stack on LAYERS palette, when padlock icon on right side of layer is gone do what you want to do with that layer.
F7 to show/hide LAYERS palette.
Palette is a set of various panels. Panels like LAYERS, MASKS, PATHS.. are very important and contains many options not available from menus. Palette is a part of workspace and by default located on the right side of screen
Align option can automatically align layers or objects. You must have at list two layers from LAYERS palette selected (blue highlight indicates that layer is selected) in order to use this function. You can for example align layers or objects to top of picture (or middle or bottom).
Open your image in photoshop, then double click on the locked layer in the layers palette and click OK in the window asking you to name the layer. The layer is now unlocked and editable.