Hi Bernhard, I manage our websites (including 'c6.csiro.au') and have some experience of your situation, as earlier this year we upgraded our server from IIS 6.0 -> IIS 8.0
I don't know the full details of what your setup is, (e.g. I am assuming you have full access to the machine, it is not 'shared-hosting', no ASP etc.) but here is an opinion: a) IIS 5.0 is less secure, less stable and has a lot more limitations - I would avoid it if possible. b) This is the most pain free option. You do have to fiddle about with the config on IIS 7.5, but once it is done the machine is easy to manage if you are used to IIS. c) As for b. d) This is also a good option - I assume you have the source code and can recompile your executables. Linux is very stable and secure. But if you have not used it before, there is more to learn, as it quite different to IIS. Happy to provide more advice/opinions outside this forum. Vincent. Vincent Fazio Materials Science and Engineering (CMSE) CSIRO Phone: +61 3 9662 7384 vincent.fa...@csiro.au | www.csiro.au Address: 343 Royal Parade PARKVILLE 3052 Victoria Australia PLEASE NOTE The information contained in this email may be confidential or privileged. Any unauthorised use or disclosure is prohibited. If you have received this email in error, please delete it immediately and notify the sender by return email. Thank you. To the extent permitted by law, CSIRO does not represent, warrant and/or guarantee that the integrity of this communication has been maintained or that the communication is free of errors, virus, interception or interference. Please consider the environment before printing this email.