win 7 64 bit driver for connecting to radio equipment via RS-232

I have a custom driver (hayes compatible) .inf file, that is used to create a dial-up connection, inorder to communicate between a PC and a radio equipment which are connected via RS-232 serial cable.
The .inf file works fine when the PC has windows XP or Vista installed. We were able to Dial successfully. But the same .inf file does not work for Windows 7 64 bit OS.

where can i get the 64 bit drivers? or is ther any other way?

The driver you have is 32 bit. It can not work under any circumstances in a 64 bit OS.

The only way to get the modem to work is to download the 64 bit driver and install. If there is no 64 bit driver, there is nothing you or anyone else outside of the manufacturing company can do about it, unfortunately.

this is s software modem. they also call it null-modem. how are these drivers actually made?

Someone with intimate knowledge of the hardware's functions and routines creates a file (the driver) that can assist Windows in speaking to the hardware. A very deep (speaking system-level) knowledge of Windows is also require.

neelima, Have you contacted the manufacturer about a 64-bit driver?

Thrax or Torrent, would it be possible for him to install it inside a virtual window like Virtual PC - XP mode?

Yes, XP mode will work well.

Contacting the manufacturer for a 64-bit driver is the ideal solution.

Another very good possibility is a virtual window.
neelima, what flavor of W7 do you have (home premium, professional, ultimate, etc)? If you have professional or higher (and at least 3GB of RAM recommended) there is a free download from Microsoft for Virtual PC - XP mode and if you install this your driver may very well function from inside the virtual window. If you have home premium then you may be able to use another product such as VirtualBox but you would need XP disc(s) and license as they are not included (They are in Microsoft's option). Please see the virtualization section of our recommended freeware.

The third, and least desirable, option is to completely reinstall W7 using the 32bit version. It has disadvantages but your license key is valid for either 32 or 64 bit versions of your flavor of windows. See here for some considerations.

As TorrentG said, Windows XP mode would work fine for this purpose.