2 External HD Backup questions

First time with an external HD backup and all seemed to go well. I followed the prompts during the preparation of the backup and burned a "system repair disk" at the conclusion.

Question 1: For scheduled backups, does the data need to be erased from the ext HD prior to subsequent backups or does it write over the earlier data?

Question 2: If my system backups are scheduled every two weeks, do I plug in my ext HD the day prior to the scheduled backup in order for it to do the job automatically?

Thanks for your help.

1. It depends on the kind of backup and, possibly, the size of the external drive.

2. Again, it depends on the kind of backup.

What kind of backup are you doing? Imaging using Windows imaging? Imaging using a third party program? Cloning? File copy? Something else I'm forgetting?

Btw, you are to be commended for going to the trouble of backing up your computer. I wish more people were as wise as you.

I believe what I backed up was a "system image" of my Win7 data. I checked the box at the beginning of the process that (recommended) allowing Windows to choose which data to backup.

I backed up onto an ex HD, size 1TB. The HD on my PC is 928MB.

First, it would really help us help you if you would complete your system specs in the lower left hand corner.

Second, I'm not familiar with Win 7's imaging tool (I use Macrium Reflect, a third party imaging and cloning tool) so someone else will have to chime in here.

Third, did you mean 928MB or 928GB?

Ooops. 928GB, of course. Thanks for the correction.