Error waiting for host service with OCR


I was trying to perform the 'Read PDF with OCR" activity but suddenly got an error:

System.Exception: Error waiting for host service. Timeout: 30000

I’ve never ever had this issue before. The full description of this is here:

Main has thrown an exception

Source: Microsoft OCR

Message: Error waiting for host service. Timeout: 30000

Exception Type: Exception

System.Exception: Error waiting for host service. Timeout: 30000

Server stack trace: 
at UiPath.Vision.Hosting.LocalHostClient.StartHostService(Int32 timeout)
at UiPath.Vision.Hosting.LocalHostClient.CreateHostServiceProxy(Boolean force, Int32 timeout, String endPoint)
at UiPath.Vision.VisionProcessor.CreateServiceProxy(Int32 timeout, Boolean force, HostingArchitecture processorArchitecture, String endPointName)
at UiPath.Vision.VisionProcessor.ScrapeUsingHostService(OCRInput input, OCROptions options, CancellationToken cancelToken)
at UiPath.Vision.VisionProcessor.Scrape(OCRInput input, OCROptions options, CancellationToken cancelToken, Boolean useHostProcess)
at UiPath.Vision.UiImage.ScrapeOCR(OCROptions options, CancellationToken cancellationToken)
at UiPath.Core.Activities.OCREngineActivity.<>c__DisplayClass36_0.<BeginExecute>b__0()
at System.Runtime.Remoting.Messaging.StackBuilderSink._PrivateProcessMessage(IntPtr md, Object[] args, Object server, Object[]& outArgs)
at System.Runtime.Remoting.Messaging.StackBuilderSink.AsyncProcessMessage(IMessage msg, IMessageSink replySink)

Exception rethrown at [0]: 
at System.Runtime.Remoting.Proxies.RealProxy.EndInvokeHelper(Message reqMsg, Boolean bProxyCase)
at System.Runtime.Remoting.Proxies.RemotingProxy.Invoke(Object NotUsed, MessageData& msgData)
at System.Func`1.EndInvoke(IAsyncResult result)
at UiPath.Core.Activities.OCREngineActivity.EndExecute(AsyncCodeActivityContext context, IAsyncResult result)
at System.Activities.AsyncCodeActivity`1.System.Activities.IAsyncCodeActivity.FinishExecution(AsyncCodeActivityContext context, IAsyncResult result)
at System.Activities.AsyncCodeActivity.CompleteAsyncCodeActivityData.CompleteAsyncCodeActivityWorkItem.Execute(ActivityExecutor executor, BookmarkManager bookmarkManager)
  • When you are using Microsoft OCR:-
    There are few prerequisites for using Microsoft OCR.

To use the Microsoft OCR you need to install MODI.
The MODI is a component of Sharepoint Designer 2007. You can directly download it from here:
After you install it, you can restart UiPath Studio and MODI should be available.

Attached some documents for reference.

Could you please confirm if the language pack has been installed properly by following the below links,

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