I'm setting up a rather involved scene with 4 Poser figures and props.  When I try and add a 5th figure I get a 'memory allocation error', and I have to delete the figure or crash.  I have 4 GB RAM (of which Vista only seems to recognize 2.5 GB).  Is there anything I can do about this?
Thanks!

Yeah, go to 64 bit os.

Or, one way to help, you can resize your textures smaller and save on memory. You really don't need anythiing bigger than 1024 unless your doeing extreme closeups. Distance shots can even be resized to 512.

Anything like PS, PSP, Gimp, you should be able to batch it all and save a lot of time. Though it only takes a few seconds to do each one anyways.

I did a test here and no problem to load 5 Vic4 with hair, cloth and body textures with no scale. Try to change the settings for your Spool Texture. The idea there in the Preferences / Imaging, Scratch Disk is tell Carrara from where to begin to use the disk as memory. With 200Mb Carrara will only begin to use the disk after get this value in RAM. Dont use low or high values, try to stay about 200.

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Are you remembering to remove your unused shaders and objects?  (file>edit>remove unused masters). Also, keep in mind that some of the newer figures, especiallly when they have all their morphs loaded, can use up a lot of memory and it's easy to hit the 2gb RAM limit.

Thanks all for the suggestions. 
Tashar-- I'd love to go to 64-bit, but I got a great company discount on 32-bit Vista through work (but not 64-bit, unfortunately.)
I do have several of my figures at a distance, so i'll make some 'smaller' textures for them and, like GK recommended, set my spool down to around 200.  (I think its defaulted to around 520 right now.)

Great, I use Vista 32 here with 2Gb RAM without problems.

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Quote - I have 4 GB RAM (of which Vista only seems to recognize 2.5 GB).  Is there anything I can do about this?

Dump Vista until Gates gets it fixed. Find an XP Platform.

Yank My Doodle, It's a Dandy!

2 gb its a system limit to 32bit OS... and the SP1 for Vista is out:

http://vistarewired.com/2008/02/07/windows-vista-service-pack-1-sp1-rtm-leaked

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Well, I turned my texture spool down to 200 and made some lo-res textures for the non-essential figures and it works like a charm!  I'm up to 6 figures in the scene now.
Thanks for all the suggestions.

PS... I had the same 2 GB limit problem with XP also.