Since rolling out Windows XP SP2 around the office network, I’ve come across curious differences in the way Internet Explorer handles file form inputs (input type="file"...), before and after SP2 is applied. At least I think I have…

Some Context.

Pre-SP2, it seemed possible to just type in a value to the input (rather than use the Browse button). For example, a user could type in ”/home/chris/my_file.txt”. In the context of our intranet, “not applicable” was a valid value that the user could enter.

The Issue.

Once SP2 was applied, this no longer worked. In our Intranet system, typing in a value produced an error in our server-side validation script – the script thought that the input had been left blank. Curiously, the page returned by the server had a javascript error warning (“Object Not Found”), despite there being no client-side scripting done on this particular page.

If the input was given a value by clicking on the browse button and selecting a file, everything would work fine.

This issue has caused us a few problems, as a few of our intranet apps suddenly “broke” with no immediate or obvious explanation.

Over to You

Has anyone else come across this little quirk? Could someone else confirm or debunk this?

I must admit to not testing this in any great depth, but I have come across this problem on a number of different pages (not all on our intranet), using a couple of different machines. I did a quick google search and nothing related came up.

Or is it all me fault? Actually, don’t answer that…