Quote - ...sometimes I get "out of memory message too!!

Ahhh Yes! One of  the dreaded not enough memory  messages.

First of all to save yourself reworking things over and over, always do a File/Save before you render. Get into habit of doing that without exception so that when you do encounter this problem all you have to do is close poser, reopen it again and then browse to your ready to render .pz3 file. In order to get your file to render, you may have to do one, some or all of the following:

1. Check the size of the shadow map for each of your lights. Sometimes they are set high and can cause problems  with memory when rendering. If that doesn't fix it....

2.  Reduce rendering bucket size to something smaller....64, 32, 16, or even 8. If that doesn't fix it...

3,  Make parts of the scene invisible using the Hierarchy Window or the Parameter Dials Properties.  Render what is left visible. Save it as a .png file.  Hide what you just rendered and make some other things visible and render that. Save that render as a .png file.  Keep doing that until you get all parts rendered.  Open your graphic program and reassemble all of your renders into one image. If that doesn't help...

4.  Browse to the folders that contains the textures you are trying to use.  Make a copy of these texture files to keep somewhere safe (because you are going to be overwriting the files in that particular texture folder in the next step). Make sure you account for the texture files for everything in your scene...hair textures, skin textures, clothing textures, prop textures.... it all adds up and eats up memory.

5. Open your graphic program. Resize each of the texture and bump map files to a maximum of 1024 pixels on the longest side.  Use "Bicubic Resampling" so that you don't blur the textures when resizing.  Click "Save" and re-save the file to it's original location.

You may still have to render in pieces and lower the bucket size even after resizing the textures.

6  You can force XP to give Poser more memory (provided you have it to give). See these threads:

http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2516735

http://www.keindesign.de/stefan/poser/3gb.html

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able to know ourselves fully as we are, especially the evil side of us.
This we can do only if we are not angry with our critics but will take in good
heart whatever they might have to say." - Ghandi