Answer
If you have upgraded from ArcIMS 3.1/4.0 to ArcIMS 4.0.1, there is a possibility that you will receive the error "Unknown ArcIMS Service" when trying to view your Web site.
![[O-Image] Unknown ArcIMS Service Screenshot](https://webapps-cdn.esri.com/CDN/support-site/technical-articles-images/000006416/00N39000003LL2C-0EM39000000wcmj.png)
One solution to this problem is to delete your existing serialization files (ArcIMSFolders.sez and ArcIMSSite.sez) and allow ArcIMS 4.0.1 to re-create them.
A. Open ArcIMS Administrator and record the following information for each Map Service that was previously created, since each Map Service needs to be re-created:
- Name (Case Sensitive)
- Map File Location
- Virtual Server
B. Navigate to the directory <drive>:\Program Files\ArcGIS\ArcIMS\AppServer and delete or rename the following two files:
- ArcIMSFolders.sez
- ArcIMSSite.sez
C. Open the Windows Services panel and stop the three ArcIMS Windows services in the following order:
- ArcIMS Tasker
- ArcIMS Monitor
- ArcIMS Application Server
D. Open the Windows Services panel and start the three ArcIMS Windows services in the following order:
- ArcIMS Application Server
- ArcIMS Monitor
- ArcIMS Tasker
E. Open ArcIMS Administrator and re-create each Map Service that was recorded in Step A above.
F. Test the ArcIMS Web site.