Frank - you should start a new thread.
No version of Windows includes native tools to manipulate existing partitions (you can create & format new ones or delete existing).
So, if you want to give partition A the space from B & C, you need to either:
- use partition magic or similar (eg partition expert). This will let you manipulate (ie combine, split, resize) partitions on the fly (but should still backup vital data first)
- backup partition A stuff (to CD or whatever). Assuming A, B and C do not include operating system, remove them (fdisk if win9x/ME, disk management if 2k/XP). Create new single partition & restore files. If operating system is on A (or B/C) - partition magic or backup/clean reinstall