This is a problem I used to have all the time with the serial port class in .NET 2.0. It was suggested that upgrading to .NET 4 would fix the problem... and it did in almos
It seems that this bug won't be fixed by Microsoft any time soon, and that there is no good workaround. I've spent over a year working on this problem off-and-on.
The solution for me was to use a 3rd party component. After testing 15+, I've found that the only one that really works is CommStudio.
The free express version is here: http://www.componentsource.com/products/commstudio/downloads.html?rv=42917