Hello All,

 On Checkbox field check, I need to display a Date Field and File Upload section.
 When the checkbox is unchecked, i need to remove the Date Field and File Upload Section..

 I have written the below code, which works perfectly when the checkbox is checked.
 When I uncheck the checkbos, it throws the error - "Visualforce Error Help for this Page
apex:inputFile can not be used in conjunction with an action component, apex:commandButton or apex:commandLink that specifies a rerender or oncomplete attribute."

VF Page
<apex:page standardController="Associate__c" extensions="AttachmentUploadController">
<apex:form >

<apex:pageBlock id="tBlock">  
   <apex:outputLabel value="Active" />  
  
   <apex:inputField value="{!Associate__c.Active__c}">  
      <apex:actionSupport event="onchange" rerender="tBlock"/>  
   </apex:inputField>  

   <br></br>
 Date of Joining <apex:inputField value="{!Associate__c.DOJ__c}" rendered="{!(Associate__c.Active__c == true)}"/>  
     <br></br>
     
     <apex:actionregion >
 <apex:outputLabel value="File" for="file"/>
 <apex:inputFile value="{!attachment.body}" filename="{!attachment.name}" id="file" rendered="{!(Associate__c.Active__c == true)}"/>  
 </apex:actionregion>
     
</apex:pageBlock>  

Apex Class

public with sharing class AttachmentUploadController {

    public AttachmentUploadController(ApexPages.StandardController controller) {

    }


public Attachment attachment {
  get {
      if (attachment == null)
        attachment = new Attachment();
      return attachment;
    }
  set;
  }

  public PageReference upload() {

    attachment.OwnerId = UserInfo.getUserId();
//    attachment.ParentId = '00190000015ZVLm'; // the record the file is attached to
    attachment.ParentId = ApexPages.currentPage().getParameters().get('id'); 
    attachment.IsPrivate = true;

    try {
      insert attachment;
    } catch (DMLException e) {
      ApexPages.addMessage(new ApexPages.message(ApexPages.severity.ERROR,'Error uploading attachment'));
      return null;
    } finally {
      attachment = new Attachment(); 
    }

    ApexPages.addMessage(new ApexPages.message(ApexPages.severity.INFO,'Attachment uploaded successfully'));
    return null;
  }

}


Please help.. 
Thanks!