Will this run on winxp pro?

DD10 can do that, DD10 does not stop other software from doing anything. Please be aware that DD10 however may not be compatible if you want to use such merged data using Win7. DD11 is out in a matter of days however so I suggest you wait and use that.

For any Acronis home user software, the license is for a single computer. If the system you use it on gets scrapped, you can transfer the license to another computer - that is no problem. But DD is not a "use anywhere" utility. It is tied to a single system. (This is my interpretation of what you were asking about in this connection.)

Good point Gary thanks

Rob-

Some additional considerations you might keep in mind...

1. Prior to doing any partition resizing activity (which a merge essentially is) you must have a complete disk image with which you can restore your system were anything to go wrong. I wouldn't even consider doing any partition resizing without it.

2. You may not want to use the merge function of DD (whatever version). It may be better to carry out what you want to do manually. For this I am assuming you mean you want to combine two partitions with "disk letters" C: and D:, and that these partitions are on the same physical drive. I am unclear as to what is meant by c + d drives in your original post. Are these two separate physical devices or two different partitions on a single physical device? If the latter, it may be best to copy D: (assuming this is just data) to an external drive, resize C: (assuming this is a system/boot partition), reboot to register changes, then copy contents of the D: partition from the external drive into the resized C:, making sure all needed registry changes for folder locations are properly carried out.

3. The above resize activity is best done running DD from bootable media, since I am assuming you will be dealing with a system/boot partition. In view of this, you wouldn't be working under XP anyway. I've done successful resizing activities running DD from bootable media, and I have yet to install DD under XP Pro SP3 on my system. If you are planning on scrapping the system, you may not have to bother with installing DD in the first place. You could just use the ISO image file available in your account when the software is registered to make the bootable media version of DD (which is what I use).