Hello.
I have a partition with 100 GB size and it is free. I want to merge it with another partition with 300 GB size that have some Data on it. Can this process remove all data on second partition?


Thank you.

gparted cannot merge partitions. You need to remove/delete the empty one and resize the other one. But it will only work if they located next to each other.
You will obviously lose every data/file on the deleted partition.

NP. On 100 GB partition, I have not any file and it is Empty but on 300 GB partition I have some files, Thus in your idea if I deleted the 100 GB partition and resize the 300 GB Partition and add this 100 GB to 300 GB partition then my 300 GB Partition become 400 GB and all files are safe. OK ?

it depends on how did you execute those steps, but basically yes, that is the process. But be careful and save your important data before start.

I attached some photos. Am I on a right track?

Attached Thumbnails

     

There are a few more contingencies and you have posted very little practical information. Are these partitions contiguous? Are they both primary partitions? Are they both logical partitions? Is one a primary and the second a logical. The link below is to the GParted Manual, check out the part under Advanced Partition Options, moving and resizing a partition.

Saw your images after I posted the above. That should work although I don't know why you are using Linux software to modify your windows partitions. Generally better off using windows to do that although GParted usually works. Your choice, your computer.

As you see in the photos they are contiguous and both are primary.

Problem Solved.
I did it and all Data are safe

that is really a good news.

1 members found this post helpful.