Hi,
I have exactly the same problem...
In a previous Post I asked how to uninstall the 'normal' FTP version which came with the DVD.
With that help I finally succeeded in uninstalling that version.
So I thought everything was clear now to proceed with FTP 7.5.
I downloaded it 4 days ago, on the 22nd of May : ftp7_x64_75.msi
So it's not the 32bit version, but the 64bit version I'm referring to...
Whatever I try, I get the same COM+ 0x80070422 error message described above.
Indeed, the DTC service is running, I even restarted it, and even restarted the server.
I searched all possible web pages with '0x80070422' but no solution relates to FTP.
Therefore I presume this is a whole new problem, may have something to do with the downloaded version itself, may be only relating to 64bit.
Any help is greatly appreciated.