Issue Resolution:

Resolution:

Click Start, and then click Run, or press Windows+R keys.
Enter Control Panel, and click OK or push Enter on keyboard.
Click on Administrative Tools, or System and Security then Administrative Tools.
Right-click Services shortcut and choose Properties.
Click on the General tab, then Change…
Select Microsoft Management Console, check the box, Always use the selected program to open this kind of file, and click on OK.
Click on Apply and OK to save changes.
Verify that Services.msc can open without issue/error.

Resolution for Issue 'Services.msc opens in a notepad window' available: Yes (Solved).
Source: Sage Community forums.
Disclaimer: Accounting File Repair Support is an independant provider of database-related services and is not affiliated with Sage or Intuit.

Services.msc opens in a notepad window: this issue or error code is a known issue related to Sage accounting products. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Sage issue to ensure minimal downtime and continue running your business. First try to resolve the issue yourself by looking for a resolution described below. If you are experiencing too many issues, you may want to migrate Sage 50 to Quickbooks. See also: do a conversion from Sage 50 Quantum to Sage 50 Pro/Premium or import Sage. If it is a complex issue or you are unable to solve the issue, you may contact us by contacting Sage Repair or by using other support options.

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