Error creating virtual disk - End of file

[dariovz]

Good evening,
I have just installed OFSMount because I have created an image of an external HD on another external HD and I would like to mount a virtual disk using the image, with extension .dd, which I have created. Unfortunately, when I click on "Mount new", after I have selected the .dd file that I want and after I have set the other parameters (in the attached picture) the system returns an error: "Error creating virtual disk - End of file". I have looked for a solution to this problem but I wasn't able to find anything. I have no experience with this software and the creation of virtual images of HD, so maybe I am making some mistake. I was following an italian tutorial, but now I am not able to go on.

Thanks,
Dario

[David (PassMark)]

The file offset value might be wrong. Where did the value 250,100 come from?
Can you try the option to "Mount all partitions" instead.

[dariovz]

Thank you for yuor answer.

I have set the file offset with a quantity just a little bigger than the size of my external HD, that is 250GB (its image is around 244 GB). However, I have tried to set it with a bigger value, but the error is the same. Moreover, I am not able to select "Mount all partitions", since it is disabled. If a click on "Select..." the system returns a warning: "No partitions were found on the image file. The entire image file shall be used as the disk size".

[David (PassMark)]

Try a file offset of zero then. I don't think using any other values makes sense.