Error Subreport could not be shown in SSRS

Error Subreport could not be shown in SSRS Issue Reason and Solution

Error SubReport could not be shown -The Main cause of this error is the SubReport Parameters Name have some difference with Main Report Parameters Name. 

Below are points to Keep in Mind while Passing Parameter from Main Report to Sub Report.

1-The Name data type of Main Reports Parameter should be same as SubReport.

2-SSRS is Case Sensitive the error is Mainly caused when your CaseParameters  of Main Report and Sub Reports are Different make sure not only the Parameter Name but also the case of Paramaters should be same.

one More Cause of this Issue which i faced I will explain you by example

I created a Main Report and Sub Report Passing Parameters from Main Report to Sub Report

with Same Name ,datatype and case also but still that error was there.

I Preview the Sub Report  separetly it was working fine

for 2 hours i was not to resolve the issue when everything is fine.

Then again i checked my Main Report

In the Main Report I select my Sub Report 

Right click-Properties -Parameters

I checked that i was manually writing the Main Reports Parameters Name instead of Selecting it from Parameters list

So I clicked on Fx 

Select the Parameter from Parameter List Did the Same for all parameters 

Preview the Report.

Finally i was able to Resolved the Issue.

3-So Keep in mind that instead of writing Parameters Name Manually it's better to Select Parameter Names from Parameters list.