eXtplorer - PHP-based File Manager

We use eXtplorer to allow presenters to upload their presentations to our ftp server. Last year, it ran flawlessly. Recently, we have started getting calls from presenters using IE8 informing us that they could not upload as they get a blank dialog box when they click the upload button. I confirmed this with one of our WinXP systems running the IE8 browser.

I ran the update and tried again. This time i found that when the empty dialog box came up, if i hit f5 to refresh the browser, then hit the upload button, the upload selection areas came up properly. The issue is that the browser has to be refreshed every time one logs into eXtplorer. Does anyone have any idea how to fix this? We have over 400 people presenting on Monday, so all weekend, our company owner will have to continue fielding these calls.

When we used it last year, we had none of these issues.

Thank you in Advance,
Bill Collins
Royal Productions