WINDOWS SERVICE
PimIndexMaintenanceSvc: Contact Data
A per-user service that indexes contact data for fast contact searching. Windows creates it from a template when you sign in and deletes it when you sign out.
TECHNICAL SUMMARY
| Service name | PimIndexMaintenanceSvc |
|---|---|
| Display name | Contact Data |
| Runs from | C:\Windows\System32\svchost.exe |
| Command line | svchost.exe -k UnistackSvcGroup |
| Runs as | The signed-in user |
| Verdict | Depends on what you use |
| Microsoft, Windows Server 2016 guidance | OK to disable (user service template) |
Paths, signer and service account observed on Windows 11 build 26300 on 12 November 2026. Run the commands below to check your own PC.
Should you touch it?
Depends on what you useMicrosoft states that if you stop or disable it, contacts might be missing from your search results, and both of its lists rate it OK to disable. If you search contacts on this PC, leave it. On the PC used for this page the instance for the signed-in user was running.
What PC Tweaker does with it
PC Tweaker does not change this service. No control in the catalogue stops it, disables it or edits its start type.
Check it yourself
See its state and start type
PowerShellGet-Service PimIndexMaintenanceSvc | Format-List Name, DisplayName, Status, StartType sc qc PimIndexMaintenanceSvcLet it start only when needed (administrator)
Note the START_TYPE that sc qc printed first, so you can put it back.
cmdsc config PimIndexMaintenanceSvc start= demandPut it back
Use the start type you noted.
cmdsc config PimIndexMaintenanceSvc start= <auto|delayed-auto|demand>
Common questions
What does the PimIndexMaintenanceSvc service do?
A per-user service that indexes contact data for fast contact searching. Windows creates it from a template when you sign in and deletes it when you sign out. It runs C:\Windows\System32\svchost.exe (svchost.exe -k UnistackSvcGroup) as The signed-in user.
Can I disable PimIndexMaintenanceSvc?
Depends on what you use. Microsoft states that if you stop or disable it, contacts might be missing from your search results, and both of its lists rate it OK to disable. If you search contacts on this PC, leave it. On the PC used for this page the instance for the signed-in user was running.
Why does the name end in random characters, like PimIndexMaintenanceSvc_67db3c?
Microsoft documents that Windows shows every per-user service as the service name followed by an underscore and a locally unique identifier for the user context. The suffix differs between PCs and sign-ins; it is not a sign of malware.
What runs in the same process?
On Windows 11 build 26300 the instance for the signed-in user shared one svchost.exe -k UnistackSvcGroup process with the per-user instances of UnistoreSvc (User Data Storage) and UserDataSvc (User Data Access). The template depends on UnistoreSvc, the dependency Microsoft's list also names.
How do I check that it is the real service?
On build 26300 the template is registered as svchost.exe -k UnistackSvcGroup and loads C:\Windows\System32\PimIndexMaintenance.dll, signed by Microsoft Windows. sc qc PimIndexMaintenanceSvc prints the template on your PC.