Ever received a "Could not load file or assembly" ... "The system cannot find the file specified" on your ASP.NET web application

Murray Gordon — Thu, 25 Jan 2007 15:17:00 GMT

Well I did, and the issue seemed to be intermittent. Here’s what it looked like for me:

Here’s what I found out.

You can read about the issue on Microsoft’s Help and Support at FIX: You may receive an InvalidCastException error in an ASP.NET-connected Web application (http://support.microsoft.com/Default.aspx?kbid=915782)

Unfortunately, there’s no immediate download or fix. You have to call Microsoft Support to find out if the secret fix applies to your scenario.

In my case it did not. I have already received a fix pack taking me from .NET Framework 2.0.50727.80 to 2.0.50727.210, which meant they didn’t have a fix for me.

Fortunately my good buddy Bill Ryan, MVP and “Master of ADO.NET” had a recommendation:

Yah, I've gotten that a bunch actually. Usually it's b/c of temp files. Clear your temp directory and give it another try. What's happening is that the temp file name generated when the assembly is loaded exceed 255 characters. So it's truncated. That in turn means that what it's trying to access doesn't exist.

Here’s a related support kb addressing the issue: http://support.microsoft.com/kb/823196

Also, set the compilation directory's tempDirectory property specifically. You can point it to C:\whatever or some shorter path name than it normally would use and thereby not have the really long path name problem.

Needless to say, that worked for me.

Thanks Bill!

And to anyone out there having this problem, hope this helps.

Thanks,

Murray

ASP / ASP.NET

Ever received a "Could not load file or assembly" ... "The system cannot find the file specified" on your ASP.NET web application