Hard Drive Problems/External Hard Drive


QUESTION: I am looking at buying an external hard drive to back up my data on my PC.  If I backup data that I already have backed up on that external hard drive will it not back it up again or will it back it up again so that I will now have duplicate data backed up?

ANSWER: Sorry ... I didn't mean to dismiss the question.

I'm not sure I completely follow what you described, but I think I see what you are asking.

If you back up to an external hard drive, it will back up the data on your C: and/or D: (or whatever letters you have and specify), creating a duplicate of that data on the external hard drive.  It will not back up the data on the external (unless you tell it to) ... the most important thing with a backup is that you have at least two copies of your important data in at least two different locations (in this case, it will be on two different hard drives, so if one crashes, your data is still safe on the other).  

Keep in mind that having a backup close to your computer will not protect your data against theft or destruction (fire, flood, etc.).

Feel free to contact me with further questions.

Good luck!

---------- FOLLOW-UP ----------

QUESTION: Maybe I didn't ask the question correctly.  Let's say I back up some photos in a file from my c drive to the ext hard drive.  Then a few weeks later I add some new photos to that same file on my c drive and then I do a back up to my ext drive.  Will the ext drive back up all of the photos in that file including the original photos so now I will have duplicates or just the new photos?

Ah ... no.  Most backup software backs up only new and changed items.  So if you add new photos to a folder, it will only back up the new ones, since it already has the old ones.  Likewise, if you have a picture that gets backed up - C:\MyPictures\photo1.jpg - then you open it, convert to black and white and save it with the same name in the same location, the backup software will know that it has been changed and will overwrite the color version with the black/white version.  Most software also backs these up in "layers" so that in our example above, you would be able to "restore" the old color version as well having overwritten the file when you saved the black and white one in its place.

Hard Drive Problems

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I can answer questions about server hardware RAID and general storage for servers and PC's - hard drive issues, troubleshooting, advice, specs, and information. While some apparent drive/RAID array failures can be recovered, I can only provide advice/recommendations in the event of catastrophic data loss. I don't assist in actually recovering from this type of data loss on this forum.


I worked as an analyst in Dell server support for 2 years, and have since worked with many Dell PowerEdge servers. I am currently employed as IT Manager. I am currently ranked in the top 5 All-Time in Server Hardware and Hard Drives in a very popular and large forum similar to AllExperts.

I have a BS in Computer Science and have earned the following certifications: CompTIA Security+, A+, Project+; CIW Web Design, Database Specialist; Microsoft Windows 7; Dell DCSE Server. I am also an expert in Windows 7, Servers, and Hard Drives (I don't normally do XP - not because I don't know it inside and out, but because I have "retired" personal support for XP, and I want to see it die :)).

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