calibre 0.7.52 not detecting Kindle

[hombre]

Again...sorry for delay..local storms knocked out everything last night...including internet connections.
Everything is now working fine on Calibre...but I would like to offer some observations.
last night , before the storms I could not convert...transfer to device was intermittent. This morning I tried to uninstall Calibre but got error messages by the handful.
My PC then crashed totally and lost all connections.
I then started to look at my protection system..ie; Comodo
A few weeks ago I ditched Kaspersky (due to what appears now to be minor glitches/problems)
This morning I ditched Comodo completely and reinstalled Kaspersky....BINGO !!!
Everything fell into place...especially Calibre.
My machine now is so slick and fast. I have tested everything I can think of and the results are brilliant. But , most of all Calibre is superb and performing so smoothly.
I'm not going to knock any particular system on here, you can form your own conclusions. But the change in circumstances is dramatic.
I would like to thank Manichean and Kovid for their help..its been a stressful weekend , but my machine is back to where it was again.

[Manichean]

What's puzzling to me is that you reported disabling the antivirus and firewall and it still didn't work. But be that as it may, it's good you got it working.