Q: Error code -43

I have the same problem. I dont' know what's wrong with it. Does anyone know??

What type (Internal HD, External USB or FW, etc) & brand (WD, IoMega, Seagate, etc) and size of HD are you using with TM ?

How is the TM backup HD attached to your system ?

How did you format the HD and did you perform a single pass of writing zero during that operation ?

Is any data being written to the TM backup Volume and how long did it take ?

I do not have anything set up to work with TM. After installing Leopard the first time I started up TM but never set anything up or did anything with it. Ever since then, I've been getting that error message.

I am experiencing the same problem.
I used a Western Digital Mybook external drive. Leopard installed with no problems.
the external drive is on and appears to be working - just can't access time machine or backups - keeps coming up
can't open - error code -43

Anyone figure this one out?

I got this error whenever the external drive, the one time machine thinks of as the backup, was disconnected. Even without starting time machine directly, when I first transferred files over from my western digital mybook, time machine assumed it was the backup and even asked to reformat it. (I'm switching back from windows and my drive format is ms-dos fat not mac os extended) I clicked no to the reformat/erase everything option without thinking about it any further. I didn't realize that TM took that drive as the backup and when it was unattached, that's when the error code started. I'd preferred it said "backup drive not attached" instead of "error code -43" but at least it didn't have that little bomb icon next to it!

To fix this, I went to the time machine preferences, by holding down the trackbutton over the tm icon and selecting preferences option that popped up.(right-clicking also works) From there I was able to designate what I wanted as a backup drive and what I didn't. that seems to have taken care of the error code -43 issue.

Looks like you're a genious. That solved the problem for me. Thanks a lot. Now I can actually set it up and use it when I get my new external hard drive! Thanks!!

Another way to fix it, is opening system preferences and click the icon of Time Machine in System row. There you can manage the hard drives that you want as backup, or just "turn off" Time Machine.-

(i´m from Spain.... sorry about my english)