A-Tools Tab disable

In some situation, A-Tools tab in Excel Menu is disable. And you need enable add-in A-Tools.
By 1:
Click File in Excel Menu --> Options --> Add-Ins --> Manage --> Disable Items --> Go --> Choose Add-In A-Tools --> Enable
By 2: Click Developer in Excel Menu -->COM Add-In--> Check Add-In A-Tools
By 3: Click Enable Add-In Excel Shorcut in your Destop