Sorry for the long title. Is it possible to have Snow Leopard in one partition and Yosemite 10.10.2 in another and copy and paste Users docs from Snowy to Yosemite? My wife needs to try to see if Yosemite "cures" some problems she's encountering using Snowy while not damaging the footnotes on a large book she's writing. Since the footnotes are VERY extensive and would be a disaster if they were disturbed, she's afraid to just upgrade to Yosemite until she's sure that the footnotes will come through unscathed. To me, the idea of copying and pasting is equally as risky as just upgrading in the normal way, but it's not my book.

The short answer is, yes, you can do this.

However, that said, if she has one copy of these footnotes, she's asking--nay, begging--for catastrophe. Any file that important should never exist in only one place, or she's at significant risk of losing them. One hard drive crash, one directory burp and they're gone.

She should have a backup, on a USB stick perhaps, or stored in iCloud...something.

She has six copies. Two on my Mac Pro and two on the desk top of her iMac and one on a flash drive and one on her Time Machine.

I'll expand on tacit's response. (Turbotax dropped support for Snowy this year [only a year after dropping support for Leopard], and I had to install Yosemite in my spare partition in order to get my taxes done, so I'm living your question.)

You can't see the Yosemite partition from within Snowy; where it's recognized at all, it's identified as "Incompatible Format".

You can, however, see Snowy from within Yosemite, and you can drag & drop files between the two, and since the d&d results in a copy in Y, the original remains intact in SL, which is in no way to mitigate tacit's remark about a backup, which is a general necessity and a particular one as respects your wife's MS, and, in fact, I'll give him a loud second..

One caveat, though: If your wife is using PPC software, it won't run in Yosemite.

Without being the least bit facetious, I'll recommend that she maintain one more copy...in a bank vault or someplace equally secure and removed from your home.

What I had in mind was to partition her only hard drive (iMac) and to install Yosemite in the unused partition. Then, I'd drag & drop her documents into Yosemite's documents folder and see what happens.

Does that sound reasonable?

P.S. The drive is 1 TB and is currently containing only 250 GB.

We planned to do that when she finally makes the last copy. We have a bank vault containing documents, but we could put a DVD and a flash drive in there as well.

Sounds perfectly reasonable as long as the pertinent software is not PPC. (You can create a new partition without erasing the existing one, and rely on your wife's TM backup - I assume it's the entire volume, not just the MS. - should the need arise.)

When you d/l the Yosemite installer it will install itself in your Applications folder, and I think it will disappear after the installation is complete if you leave it there, so before you run it, drag it out of /Applications to your desktop or some-such (against future need).

Having two copies of the MS on the same HDD offers protection against corruption, but none against disk failure.

And having all the existing copies in one physical location offers no protection at all against myriad possible disasters, so a bank vault copy is a necessity...RIGHT NOW!

I'll suggest two thumb drives rotated on a weekly, or more frequent if necessary, basis.

Edit: Don't forget that TM will not back up the Yosemite partition, so you'll have to plan ahead in that respect.

true that. backups need to provide protection from things such as "fire / flood / tornado / theft / vandalism" as well as their other motives, and that generally requires the backup to be off-site. Of course other issues (such as convenience and currency) don't work well with offsite, so you usually need two backups, one local (time machine) and one offsite. (any good recommendations?)

"Give me a minute here, I really need to find that hard drive..."
http://abcnewsradioonline.com/storage/news-images/GETTY_111913_WashingtonTornado.jpg

I appreciate the suggestions here. However, there is a lot I haven't told you. For example, the book is changed daily and sometimes several times daily as she see something else that needs improvement. Our storage methods work for us given the circumstances. I am always present when our computers are on. Otherwise, they are off. I have my own projects that need attention. I do not currently use any external storage services, including iCloud. That will change when the copyrighted documents are in a publisher's hands and the patentable discoveries have been filed.

To make matters worse, my dear spouse has declined my offer to try her work on Yosemite as described earlier in this thread. She will continue to slog along in Snowy until she is finished.

I appreciate the kindness and obviously good advice given thus far and I deeply regret that I cannot continue to bring this thread to a successful conclusion. If I had had any advance inkling that the results of my original post would be declined, I would not have posted it. Best regards.

Hahahaha.

Not a bad plan…stick with what you know…don't change horses mid-stream, et cetera.


Successful conclusion or not, there was a lot of good information that got "out there"…..which is its own success.

I live in the mountains. Tornados and the like are virtually unheard of with one tiny exception.

Sorry, but I'm going to continue beating the horse and hope it isn't dead yet.


Your "circumstances" do not include the unexpected.

Heck... Hide the thumb drive in a coffee can in your garage so it's readily accessible whenever you need it!

Your projects sound way to important, and with too much time invested in them, to leave them vulnerable to Murphy.

This will be my last post on this thread. Please go back and look at the first entry. That was my question. Then, the gang started giving advice about how I should protect the project. In an effort to please people whom I respect and like, I started giving you little glimpses of what I've done and what I'm doing in the hope that you would be satisfied. Look at all of the comments. They assume I don't know squat about protection of valuable property. That is not true. At no time have I told you everything I'm doing. It's too risky. I regret saying anything. I will thank you all to quit bugging me about it. It is my business and I know what I'm doing. Ample protections are in place. End of story!