we are going to install IE8 in the company. We have many web based ASP.net applications. I would like to evaluate the impact of installing IE8 on our asp.net applications. the applications are using .net 2.5 and 3.5. They use ajax in some cases.
I have never done such impact analysis so what is the best approach?
The approach is to run these applications in IE8 and see what happens.
After that you will write down what works and what breaks and attempt to estimate:
That should give enough information to management to decide on how the migration will proceed.
The first question I would ask is whether you have a compelling reason to move to IE8?
There are many websites that don't work (the whole reason that IE8 has a "compatibility mode"). The chances that you have done some of the same things these websites do to make them "incompatible" is fairly good.
There is no way around a need to thoroughly test your own applications before making the move.
We found that the move to IE8 actually broke some things in Visual Studio (seems it's a known issue) so didn't even get as far as starting to test the applications.
I am IE user and use Vista and develop in VS2008. IE7 became almost unusable and actually changed my default browser to Firefox. This caused more issues for me since I use msn hotmail and other things that seem to work together quite well (MS passport etc) I was also sceptical about upgrading to IE8, but did it. its better! I would suggest upgrading to IE8 and fixing what needs to be fixed anyway.
I'd push out IE8 and change the IIS headers to force IE7 Compatibility mode by adding the following meta tag (the opening < and closing /> are removed so that the string could post):
meta http-equiv="X-UA-Compatible" content="IE=EmulateIE7"
Make this change on all of of your ASP.NET sites. Then, as a site is updated to work in IE8, remove the header and IE8 will run in standards mode.