PHP export to Excel opens twice

Question

I'm using the Spreadsheet_Excel_Writer plug-in to perform a data export from a PHP web app. All has worked well for quite some time now, but my client just informed me that in the last couple days the export behavior has changed: the downloaded file opens in Excel, then starts a new Excel instance and opens again. If you try to edit either one, it refuses claiming the file is locked. It's not a game stopper, but definitely annoying.

They tell me the only change of late was upgrading to XP SP3. Browsers are IE7 and IE8.

Any ideas where to look first?

Answer 1

My client had some IE problems with cached instances of same-name exports. So, to alleviate that, I added a random string onto the exported filename, carefully keeping the xls extension.