When even Linus Torvalds is heaping sardonic praise on Windows 7, you know Microsoft must be doing something right. But the gloss was definitely starting to come off for my colleague Stuart Turton and I over the past week or so.

For some unfathomable reason, Word 2007 was really starting to struggle – letters would appear on screen an annoying second or so after you typed them, and scrolling through long documents produced more jerks than an X-Factor audition. Not an ideal scenario for harassed journalists on press week.

Word’s not usually the first application to exhibit performance problems. If your processor or memory are being pushed to breaking point, you’d normally expect 3D games or DVD playback to be suffering from the heebie-jeebies first – but both those applications were fine on our systems. A performance widget on my desktop also confirmed that the processor and 3GB of memory in my laptop weren’t being unduly burdened by Word, either.

 A quick straw poll of the office revealed that only Stu and I were suffering from Word Arthritis – with the rest of the team quietly assuming there was actually nothing wrong with our PCs and that it was just the news team having a deadline-induced meltdown.

After ruling out everything from Aero Glass to graphics drivers it finally dawned upon us – we were the only two running the Windows 7 trial version of Kaspersky Anti-Virus. A quick uninstall later, and Word was back to its normal responsive self on both our systems. What’s more the odd juddering Aero Glass animation and occasional problem with saving files to our office network appears to have disappeared, too.

We’re not going to be too hard on Kaspersky: this is a free prototype security suite running on a beta operating system. Bugs are to be expected. And unlike AVG, at least Kaspersky hasn’t got the brass neck to charge for protection of a beta OS.

But although we probably shouldn’t say it, we’re rather enjoying the liberation of being free from the constant nagging and annoying slowdown of our Russian minder. Can we live without security software on the office network? Probably only until our IT manager notices.