wootah
Basically the accurate post from cradom shows a major difference between Mac and Windows: the file system.
https://en.wikipedia.org/wiki/File_systems
Dell do have a special recovery partition, but this has never been an issue with READING from any Mac with OSX that I have used.
If you are using USB with the drive removed from the Dell, you shouldn't have any issue.
As you seem to want to access it from a NETWORK, you first need to enable sharing on the Windows machine.
This option may be disabled if it is a corporate build machine.
Normally you would do this:
To share a drive or folder on the network
1. Open Windows Explorer, and then locate the drive or folder you want to share.
2. Right-click the drive or folder, and then click Sharing and Security.
• If you are sharing a drive, on the Sharing tab, click If you understand the risk but still want to share the root of the drive, click here.
• If you are sharing a folder, go to the next step.
3. Do one of the following:
• If the Share this folder on the network check box is available, select the check box.
• If the Share this folder on the network check box is unavailable, this computer is not on a network. If you would like to set up a home or small office network, click the Network Setup Wizard link and follow the instructions to turn on file sharing. Once file sharing is enabled, begin this procedure again.
You'll have to name it so you can see it, making it easier to see from the Mac over the network.
On the Mac Finder menu (where you see all the folders) use the connect to server option from the Go menu - or CMD + K
You will probably need a SAMBA share name e.g. smb://dellserial
Find your Dell on the network, connect and wait. The drive will be attached underneath.