ION_Network database doesn’t upgrade throwing an “Insufficient Disk Space” error

Issue:

During a Side‑by‑Side (SBS) upgrade, the ION_Network database upgrade may stop immediately with:

“Insufficient disk space”

This can occur even when the server has plenty of free space.

Product Line:

Power Monitoring Expert 9.0

Power Monitoring Expert 2020

Power Monitoring Expert 2021

Power Monitoring Expert 2022

Power Monitoring Expert 2023

Power Monitoring Expert 2024

Environment:

PME Upgrade

Cause:

The failure is triggered by one of the following conditions:

1. Actual disk or tempdb space limitations
   SQL Server requires significant temporary working space during schema transitions. If the drive hosting ION_Network or tempdb is constrained, the upgrade will terminate with this message.

2. Unexpected objects in ION_Network
   SBS upgrades require a clean database schema.
   If the database contains leftover or custom objects, the upgrade validator fails immediately.
   A known example is the presence of an unexpected table, such as:

   ION_Network.dbo.SchedulerTick
   

Resolution:

1. Verify and increase disk space
   Ensure sufficient free space on the disks containing:

   • ION_Network.mdf / .ldf
   • tempdb.mdf / .ldf

2. Remove invalid SchedulerTick table (if present)
   Delete the unexpected table using SQL Server Management Studio and run this:

   DROP TABLE [ION_Network].[dbo].[SchedulerTick];

Then re-run the upgrade.

Recommendation: