incompatibility with 64 bit windows

[RAK]

Without making any changes to an exe that is 32 bit - Windows is suddenly preventing the exe from running. A message is displayed that it is a 16 bit program and is not compatible with 64 bit windows. I have recompiled (32) and there is no change. This issue appears on multiple machines in different locations.
Is it possibly an old dll in the exe causing this? There are 2 exe's. One is an updater. When I run the updater - the message appears and then the main exe will not run. If I re-compile the main exe - it runs fine until the updater is started (displays message and does not run). After that - neither exe will run unless I re-compile.

[RAK]

Strange issue but it is solved..

The updater runs an HTTP exe download and the site was down. For some reason - it triggered the 16 bit message. We fixed the server and the message is gone! All is well..

[td]

I have never encountered the 16-bit error while executing one of our products but I have experience it with other products that are clearly 32-bit.  Probably some kind of minor bug in the Windows kernel is causing an inappropriate error message to be generated under a certain set of conditions.