If you are using Mozilla Firefox, you shouldn’t have any problems with MassTransit Web Client on 64-bit Windows and Mac, since all current versions of Firefox released by Mozilla are 32-bit. For information about how to configure the HTTP transfer method, see the 'Windows Web Configuration Instructions' document on the MassTransit Latest Releases page. To use HTTP click, the “Switch to use HTTP” link on the Send Files or Download Files page. If you do not want to switch your browser to 32-bit mode and the HTTP transfer method is available on the server, you can use it to transfer files with the MassTransit Web Client. However, you can use the MassTransit Web Client plug-in on a 64-bit operating system by running the browser in 32-bit mode. MassTransit Web Client plug-ins prior to version 7.0.1 are not supported for Internet Explorer and Safari browsers running in 64-bit mode.
Currently, versions 7.0.1 and later of the MassTransit Web Client plug-in (available for the latest MassTransit HP 7.0.1 and later Servers) is supported for Safari in 64-bit mode but it is not supported for Internet Explorer running in 64-bit mode. MassTransit Server is supported on Windows 64-bit platforms.