Are you using Time Machine for the backup?
If so it should have no trouble. Over wireless and especially on Lion could be issue.. but the backup itself not so.
Is this initial configuration? ie had one working for ages and added a new computer.. spell it out a bit?
Also spell out the exact problem. We cannot work with no info.
A1 install the widget so you can get log of faults.
Yes, I'm using time machine for back up. older MacBook Pro with Snow Leopard was working fine since November 2011. In January I added a new Mac Book Pro with Lion. During intitial backup of second machine it said their was a problem with the backup and coudnt contimue. Sorry, I did not take a screen shot of the actual comment so can't remember exactly what it said. First machine was on auto backup but then one of the back ups took forever which was out of character for intermediate backups. So I turned off time machine on both machines. then I turned on time machine maually for the older machine and it requested to redo the initial backup so I'm letting it do that. But before I begin to back up the new Lion MacBook Pro, I want to make sure I'm not doing something wrong on itnital back up of a second machine.
No I would not do installs of the widget half way through something.. not that is does anything directly to TM but I think it is not worth messing the backup.
It sounds like you are doing initial backup over wireless..
Lion has some networking issues, where it forgets its marbles.. it seems to forget where the TC is, even if it has internet connection through it. Hence why it failed.
Do the initial backup over ethernet.. that is faster and far less likely to lose connection or corrupt.
If it fails then the widget will give you some idea of what is happening.
I will back up with ethernet now, I forgot to do that and it stopped backing up on the snow leopard machine have way throuogh. This is from the widget, I'm not sure what this means but looks like it got fouled up while copying imovies:
Copied 116.0 GB of 216.9 GB, 218182 of 749393 items
Error writing to backup log. NSFileHandleOperationException:*** -[NSConcreteFileHandle writeData:]: Input/output error
Error: (-36) SrcErr:NO Copying /Users/lutherweber/Movies/iMovie Events.localized/Manasas Park Away/mamos party/clip-2011-02-19 16;43;03.mov to /Volumes/Time Machine Backups/Backups.backupdb/Luther Weber's MacBook Pro/2012-03-29-184013.inProgress/9A7648F2-847D-4902-874E-F0F00EF2A8FB/MacHD/Use rs/lutherweber/Movies/iMovie Events.localized/Manasas Park Away/mamos party
Ok, I think you need to run a verify disk on the computer before you try and backup again.
And either verify the TC or start again.. just wipe it, if you haven't had a single successful backup and all attempts are by wireless. Erase and start again.. IMHO.. others will suggest just the verify but enough goes wrong that unless you are actually prepared to test the back.. and the only way to do that is a full restore.. it is nice to know the first one went complete in one go.
I just discovered something. when I was checking a separate archive drive (not Time Capsule) to see if I had archived this imovie file, I noticed that the contents of the imovie event adn project folders stopped at teh same place that the time Capsule just stopped. ie only halof of the imovie file had transfered to my other archive drive. I don't know if there is a connection. Do you know if imovie on Lion will accept and play clips and movies made on snow Leopard if the content folder is located on an external hardrive?
. . .
Error: (-36) SrcErr:NO Copying /Users/lutherweber/Movies/iMovie Events.localized/Manasas Park Away/mamos party/clip-2011-02-19 16;43;03.mov
There's a problem with that file (error -36 is an I/O error). Exclude it, per the blue box in #C3 of Time Machine - Troubleshooting.
Assuming the backup then works ok, you'll need to figure out what's wrong with it; perhaps you can reload or copy it.