Using the vSphere web client, select the virtual machine. For example, select vCenter Management and in the navigation tree on the left select the virtual machine.
In the inventory, click Datastore and on the Objects tab, select the datastore to which you will upload the file.
Click the icon.
Select the folder that you created or select an existing folder, and click the icon.
If the Client Integration Access Control dialog box appears, click Allow to allow the plug-in to access your operating system and proceed with the file upload.
On the local computer, find the ISO file and upload it.
Once the upload has finished, refresh the datastore file browser to see the uploaded file in the list.