> I write my apps in D2007 with Firebird server. One of my customers has 2
> PCs, Windows XP home edition. One PC has Firebird 2.03, the other one runs
> the same app over the Intranet (TCP/IP - file sharing). Everything works
> fine, until I upgrade Firebird 2.03 to 2.1 (newest release).
>
> From that moment, the PC with the FB server shows this message:
> <<<
> R6034
> An Application has made an attemp to load the C runtime library incorrectly
> Please contact the application's support team for more information ...
>>>>

Install MSVC8 run-time package or install FB 2.1 using official installer.

Regards,
Vlad

PS And *read* installation notes