Just as a tip,
my method for testing different versions of Csound, and keeping
several versions on my system is by renaming.
So my "current" Csound installation resides in "Program Files/Csound".
Whenever I want to test another version, I rename my current Csound
version to (for example) "Csound_currently_in_normal_use", and then
make a new empty directory at "Program Files/Csound" and copy the test
version to there. If I use/test a binary installer, the only thing I
*must* remember is to rename my currently working version to something
else before installing.
Without a relatively safe method of going back and forth between
versions like this, I would never dare to test new versions, in fear
of messing up my production system.

Oeyvind

2008/9/16 Art Hunkins <abhunkin@uncg.edu>:
> Unusual new behavior upon doing above install.
>
> I have a special pared-down version of of Csound 5.06 installed in a single
> folder, with my .csd files running (in Lettuce) completely within this
> folder. No environment variables are needed or desired. Everything works
> fine.
>
> I install 5.09 from the installer in a different location, complete
> (unfortunately) with a set of environment variables. These variables,
> especially OPCODEDIR, prevent my 5.06 system from running. The 5.09
> environment variables take over, look for everything in the 5.09 folders,
> and tell me everything is an incompatible version. (I expect that it's
> OPCODEDIR pointing to 5.09.)
>
> To my knowledge this never happened before. The environment variables did
> *not* "take over" my self-contained 5.06 installation.
>
> I really need to be able to run from a single folder regardless of what
> other Csound installations may be on a given machine, or regardless of what
> the environment variables are (I'm in XP here).
>
> My understanding is that first Csound looks for everything in the current
> directory, and only if it does not find what it needs there, looks elsewhere
> (according to environment variables). This does not seem to be happening
> with 5.09.
>
> Please someone (Michael?) straighten me out.
>
> Art Hunkins
>
>
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