[sanuj_bhatia_54]

I am having difficulty in backing up my data! I have a Seagate Backup Plus..but time machine shows that it isn't in some form that supports mac ( jouneled form..idk). Please tell me that does installing Yosemite beta results in data loss?

[Beyond Fire]

Time Machine should allow you to format your HDD to the proper format for MAC OSX. That being said installing the 10.10 beta itself will not cause any data loss, but I highly recommend you do NOT install the beta without a backup. If you end up having to restore back to 10.9 then you will lose everything that was not backed up via Time Machine.

[sanuj_bhatia_54]

Time Machine should allow you to format your HDD to the proper format for MAC OSX. That being said installing the 10.10 beta itself will not cause any data loss, but I highly recommend you do NOT install the beta without a backup. If you end up having to restore back to 10.9 then you will lose everything that was not backed up via Time Machine.

By format do you mean that my all the data on external Hard disk will be erased?

[Tilman Mueller]

By format do you mean that my all the data on external Hard disk will be erased?

Exactly. That's what "reinitialize / format a hard drive" does. As the name implies

But if you did a backup before via TM, you are fine. During the installation of OS 10.10 there's no data loss on your actual drive because it's basically "an update".

Hope I could clear things up a little bit.