Please provide domain admin permission to the installation folder of ADManager Plus and check for the issue if not please follow the steps provided below.
1. Stop ADManager Plus (Click on Start--> All Programs --> ADManager Plus --> Stop ADManager Plus).
Note : In case you have installed ADManager Plus as a NT Service, stop the service (Start --> Run --> type services.msc ---> Stop "ManageEngine ADManager Plus" ).
2. To start ADManager Plus as a service: 1. Stop ADManager Plus (Start-->All Programs-->ADManager Plus-->Stop ADManager Plus). 2. Start-->All Programs-->ADManager Plus-->NT Service-->Install ADMP Service. 3. Start-->Run and type "services.msc". 4. Right-click on "ManageEngine ADManager Plus" and select Start to run ADManager Plus as a Service.
3. After ADManager Plus is installed as service, kindly configure the service account with Domain Administrator privilege by following the below procedure, Step 1: Click on Start->run->services.msc Step 2: Locate the service name "Manageengine ADManager Plus" Step 3: Right click->Go to Properties->Log On Step 4: Select "This account" and provide the credentials.