C++ Builder安装经验:与Delphi数据库的协调
  在已安装了Delphi 3的机器上安装C++ Builder,会发现安装完后Delphi 3的数据库
转不起来了。。。。
解决办法是:用regedit 把HKEY_LOCAL_MACHINE\software\Borland\Database Engine
下的DLLPATH里指向C++Builder的BDE的路径删掉, 只留下指向Delphi 3的
BDE的路径,就万事大吉了. 当然前提是别把两个BDE装到同一个目录下.

下面是Borland自己的解决方案原文.

Frequently Asked Questions

BDE Version problems

Question:
I have more than one installation of the Borland Database
Engine and I am having troubles configuring the BDE to work
with either Delphi, C++Builder, or IntraBuilder.

Answer:
Run regedit to see what your current path is for your DLLPATH
under HKEY_LOCAL_MACHINE\software\Borland\Database Engine.
There should be one and only one path for this key. If
there is more than one, it will result in problems.
Furthermore, the CONFIGFILE01 key should point to your latest
config file.

One way to resolve problems arising from
conflicting installations of the database engine is to
reinstall the version of Borland''s compiler or
tool (either Delphi, Intrabuilder, or C++Builder) that has the
latest version of the BDE. Then edit the DLLPATH in the registry so
that it uses the default that the installation program gave.

This works because the latest version of the BDE is backward
compatible which means that it will run applications written
with previous versions of the BDE.