Samsung Galaxy Tab 10.1 — Firmware Update Failed due to "network or server problem"

I recently pulled my Samsung Galaxy Tab 10.1 off the shelf, factory reset it and wanted to update the firmware to something that's 4.1 or higher to support the Amazon App Store. I'm stuck back on Android version 3.2. When I go to Settings>About Device>Software Update>Update, it gives me an error that says "Failed to update firmware due to network or server problem. Try software update later...". I'm connected to wi-fi. I've "tried it later" and it gives the same message. I don't currently have a sim card in it. Is there another way to manually update the firmware version to something the Tab 10.1 will support? I appreciate the help!