I have a namespace like this in one of my aspx pages (.NET 1.1)
<%@ Register TagPrefix="jwg" Namespace="Janus.Web.GridEX" Assembly="Janus.Web.GridEX" %>
This code used to run alright in .Net 1.1 on a 32 bit system but recently we are porting it to 64 bit system (only the run time not the development environment). It has already been ported successfully on one 64 bit system - however that was done like months ago and I have now completely forgotten what all settings were done at that time (and unfortunately I did not take any notes at the time).
Everything runs fine except for few pages where I use the above mentioned namespace registration tag. It is throwing me a script error error at run time from browser saying that An error has occurred in the script on this page. Error: 'GridEx' is undefined. Do you want to continue running scripts on this page? The DLL in the bin is same as it is in on the another 64 bit working box. All other setttings on IIS seems to be working fine since I was able to set .NET 1.1 app pool on it and run the entire application.
In the Visual Studio I removed all the references and created them once again (choosing the path to bin directory of the project) and this resolved this issue... What was probably happening that even though in properties of the references it was showing the path to bin, but somehow the whole thing needed to be refreshed to reflect it into the compiled project file. Its Visual Studio 2003.