Like most of you, I install multiple versions of various products. Until disk space runs out. C4D is one of the main space killers but only because of its huge library addons. So I looked around trying to find a way to save space. No suggestions in its documentation but something I read in it, sounded like it would help. So far it has, though I don't know if it will work for all possible scenarios. The following is for people with multiple C4D platforms and lack of disk space. For a single platform, it would be a waste of time. 1) Make a folder in the root of some disk partition with lots of free space in it. As an example, name it C4Dlibs. 2) Not necessary but convenient, make this new folder shared. Its shared name will end to be something like: \\mycomputername\c4dlibs 3) Copy into C4Dlibs, the libraries (*.lib4d) from the latest C4D version you have (at the moment R20). These libraries are in: \Program Files\MAXON\Cinema 4D R20\library\browser 4) Change the suffix of the original libraries you copied (say *.lib4d.hide) or easier, move them out of there and into some backup disk. 5) Do the same as in (4) for the same libraries in the other versions of C4D. 6) Create a User environment variable called: C4D_BROWSERLIBS and assign the shared folder name to it. e.g. C4D_BROWSERLIBS=\\mycomputername\c4dlibs That's it. Run R20 and it should work as before. Run the earlier versions and they should work using R20's libraries (from step 3). If you happen to copy to the new folder any libraries specific to some 3rd-party plugin (e.g. like vray libraries for R19), they'll show in the Content Browser but they will not work since the proper plugin is missing from that platform (R20). They'll still work if you run R19 of course. You can ignore these libraries in the Browser, or just keep them in their original folder so you see them only when they can be used.