The IMA service running is necessary for the discovery of the XenApp server, XenApp functionality and for normal operability of XenApp. In the registry, you can see the CurrentlyLoadingPlugin string to identify if the issue is related to the datastore.

Check if the IMA service is started. If not started see the error message that may help to find the root cause.

Use the registry editor and look at the following registry string:
\HKLM\SOFTWARE\Citrix\IMA\Runtime\CurrentlyLoadingPlugin. In 64-bit \HKLM\SOFTWARE\Wow6432Node\Citrix\IMA\Runtime\CurrentlyLoadingPlugin.
If the IMA service fails to start and this value is blank or not present, the IMA service could not connect to the datastore or the local host cache is missing or corrupted.

Procedure 1
Check the database connectivity and authentication by using the Windows ODBC Configuration. Select the System DSN Data Source and click Add to add a new datasource. If we get connection failed error message then the database authentication and db_owner roles needed to be set on the database in the SQL server. Address the connectivity issue and attempt to restart the IMA service.
Procedure 2
Run the XenApp Role manager in XenApp 6.0 to reconfigure your XenApp Configuration. Select Edit Configuration in the XenApp selection. Click Create new server farm or Join an existing server farm. Creating a new database and Farm will rule identify existing farm as problematic. Join an existing working farm if you have a working farm but better create a new farm to address the issue. When the server farm was recreated and configured, the IMA service started and the appropriate registry entries were present

If there is no connectivity between the SQL server and the Local Host Cache, we need to configure it once again to establish the connection to work again normally.

1. Run the below command:

dsmaint config /user:username /pwd:password /dsn:dsnfilename

2. Stop the IMA service

3. Recreate LHC. dsmaint recreatelhc

4. Start the IMA service.