Hi Bhavesh23,

Refer below article.

The Controls collection cannot be modified because the control contains code blocks (i.e. ... ).

Bhavesh23 says:

when i applied this script line into my master page heading its occur error while open crystal report. 

 

1	<script src='<%=ResolveUrl("~/crystalreportviewers13/js/crviewer/crv.js")%>' type="text/javascript"></script>

 

this below error is occur while open crystal report.

1	The Controls collection cannot be modified because the control contains code blocks (i.e.

 

 its done when the script line put after body close tag.