OneDrive Not Opening After Migration

The migration finished on Friday. On Monday, users say the OneDrive cloud icon is gone and nothing happens when they open the app. Some see a blank sign-in window. Others see the old account and a sync error.

I get this ticket after almost every tenant move. This guide shows why OneDrive is not opening or not starting after migration, how to fix it in six steps from Microsoft's own pages and what admins should check before users sign in.

Why is OneDrive Not Opening After a Migration?

A migration tool copies files between two tenants in the cloud. It never touches the sync app on the PC. So the sync app still holds the old account, old saved sign-in data and sometimes old policies from the source tenant.

Microsoft's page on OneDrive not starting names one clear cause. A Group Policy setting on the computer can stop OneDrive for work or school from starting. The symptoms are no sign-in prompt and no sync, with no error shown.

In my experience, three things cause most cases after a move. First, a policy left over from the old setup. Second, an old account that is still linked. Third, a damaged sync state that only a reset can clear.

Which Cause Fits What You See?

Match your symptom to a fix before you change anything on the PC.

How do You Fix OneDrive Not Opening After Migration?

Work through these steps in order. They go from the safest check to the deepest one. Microsoft says unlinking and re-linking loses no data, and a reset does not delete files either.

1. Start OneDrive by hand. Select Start, type OneDrive and open the desktop app. If a sign-in window appears, sign in with the new account and skip the rest.
2. Check the policy value. Open the registry key HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\OneDrive and look at DisableFileSyncNGSC. Microsoft says a value of 1 stops OneDrive for work or school from starting. Back up the registry first and ask your admin to remove the policy.
3. Unlink the old account. Open OneDrive settings from the cloud icon, go to the Account tab, select Unlink this PC and then Unlink account.
4. Clear saved sign-in settings. Press the Windows key and R, enter %localappdata%\Microsoft\OneDrive\settings and delete the file PreSignInSettingsConfig.json.
5. Reset OneDrive. Press the Windows key and R again and enter %localappdata%\Microsoft\OneDrive\onedrive.exe /reset. If Windows cannot find it, try the Program Files path from Microsoft's page. Then start OneDrive from the Start menu.
6. Sign in with the new account. When OneDrive says a folder already exists, select Use this folder. Then choose your folders again if you used selective sync.

Microsoft's page on resetting OneDrive says a reset disconnects all sync connections and then starts a full sync. It also says you must choose selective sync folders again for every account once sync finishes. Its steps also list wsreset.exe before the reset command.

Microsoft's page on unlinking and re-linking OneDrive says files sync back as placeholders, so it can take a while.

What is the DisableFileSyncNGSC Policy?

It is a registry value under the OneDrive policy key. Microsoft says that if it is set to 1, OneDrive for work or school does not start. The page lists these symptoms: no sign-in prompt, no sync and no error.

Be careful here. Microsoft warns that if you delete the value without your admin changing the policy, the policy returns at the next restart, sign-in or periodic update. OneDrive then stops starting again. A Group Policy Object that sets it must be changed by the admin.

If you use the Store version of OneDrive, Microsoft gives other reset steps. Select Start, type apps:onedrive and press Enter. Then select App settings and scroll down to Reset.

What should Admins Check Before Users Sign in?

Do the checks in this order. Check policies first, then the sign-in, then the data.

First, look for old Group Policy or registry settings from the source setup, mainly DisableFileSyncNGSC. Second, tell users to unlink the old account before they sign in to the new one. Third, confirm the files exist in the new tenant before anyone resets a PC. Fourth, keep the source tenant read-only until every user is back online.

RecoveryTools OneDrive Migrator copies OneDrive for Business accounts between tenants, keeps original dates and hash checks every file. Sync app and Files On-Demand settings are not carried across, so users sign in to the new account and choose their folders again. For sync problems after sign-in, read OneDrive not syncing after migration. For backup folders, see Known Folder Move after migration.

For the move itself, read how to migrate OneDrive from one tenant to another and OneDrive cross-tenant migration. For old file versions, see OneDrive version history after migration.

What are the Best Practices After a OneDrive Migration?

• Send users a short note before cutover. Tell them to unlink the old account and sign in with the new one.
• Check policies before you reset PCs. A reset cannot fix a policy that blocks the app.
• Test on one PC first. Confirm the steps work before you send them to everyone.
• Keep the source read-only. Users can still reach their old files while they sign in again.
• Help with selective sync. Tell users to choose their folders again after a reset.

Which Mistakes Make OneDrive Problems Worse?

Four come up often. First, deleting the policy value without your admin, so the policy returns at the next restart. Second, resetting before you check that files exist in the new tenant. Third, signing in with the new account while the old one is still linked. Fourth, assuming files are lost when the app simply cannot open.

My Verdict on OneDrive Not Opening After Migration

The files are almost always safe. The problem sits on the PC, in a policy, an old account or a damaged sync state.

Check the policy first, then unlink, clear the saved sign-in file and reset. After that, sign in with the new account and choose your folders again.

Frequently Asked Questions

Published 17 October 2026. Steps come from Microsoft's pages on OneDrive not starting, resetting OneDrive and unlinking and re-linking OneDrive. Product behavior comes from the RecoveryTools OneDrive Migrator page. Microsoft can change these steps, so check them before you plan.