ServiceDesk Plus MSP Edition Complete Helpdesk for MSPs

Please read the below points and then proceed with the upgrade.

Once you apply the service pack, you cannot revert to the older version. Hence we recommend you to apply the service pack on a test set up first.
Take a backup of your production data and restore it in a test setup. Then apply the Service pack in the test setup and check your older data.
Users in Build Number 8200 and 8201 alone need to change the Updatemanager files as mentioned below.
UpdateManager.bat (Download Windows users) | UpdateManager.sh (Download Linux Users) and replace it under <product_home>/bin folder of your current installation.
Please note: After applying a service pack, start ServiceDesk Plus MSP, login through the Web UI and shut it down before applying the next service pack.

Migrate from Build 10538 to 10600	Windows - Service pack SHA256 Value - f275e758ef5f55411ef55e8f3f9f3bc69e2e19a83ed1645c193b99fe385b062a Linux - Service pack SHA256 Value - 2e3373567da9f473d63355f8d0ce5bc73967f52c70c56690885a5af2c84b9e23 How to Install \| README
Migrate from Build 10500,10501,.. 10537 to 10538	Service pack \| How to Install \| README SHA256 Value 70a35ccdf5993722838e013f4a98b44e25b2151eaea5ecf10b43ad3f8752d605
Migrate from Build 9427 to 10500	Windows - Service pack Linux - Service pack How to Install \| README
Migrate from Build 8300,...8315 to Build 8316	Service pack \| How to Install \| README
Migrate from Build 8201,...8211 to Build 8300	Service pack \| How to Install \| README
Migrate from Build 8200 only to 8211	Service pack \| How to Install \| README
Migrate from Build 8106 to Build 8201	contact : sdpmsp@manageengine.com \| README
Migrate from Build 8100, 8101 to Build 8106	Service pack \| How to Install \| README

The older builds are available here.

Shut down ServiceDesk Plus MSP application.
Make sure the product and the database is stopped properly. You can check this from the task manager. It could take upto 5 minutes depending on your hardware configuration. If the database has not stopped, execute stopDb.bat/.sh from/bin
Run the script UpdateManager.bat (UpdateManager.sh for Linux) in the /bin folder. This opens the Update Manager tool.
Click "Browse" to select the Service Pack file (ManageEngine_ServiceDesk_Plus_MSP_8_2_0_SP-x_x_x.ppm file that you had downloaded) and then click "Install...".
Follow the on-screen instructions to apply the Service Pack / Hotfix.
Once the upgrade is complete, start ServiceDesk Plus- MSP Server.

Refer to this link for detailed instruction on Upgrade

In the ServiceDesk Plus web client, click the "About" link on top right of the page.
You should see the Build number mentioned on the top right of the page.
Check the following image guide to locate the build number.