Google Apps Script: We're sorry, a server erro

Question

I have received 341 error notification emails for the below error

We're sorry, a server error occurred. Please wait a bit and try again.

The notification email only tells about the name of function in which the issue is occurring.

The script is not running now. Any try to run any function in the script gave the above error. Also my custom menu that i have added into the Spreadsheet using the script is gone. I found no way to debug the script as every action on the script giving me the above error.

EDIT

Below is the function in which error is coming

function crunchEmails() {
  var sheet   = SpreadsheetApp.getActiveSheet();
  var gLabel  = sheet.getRange("gmailLabel").getValues();


  // check the current SpreadSheet for limits and create a 
  // new SpreadSheet if limits are approaching
  checkSpreadSheet();


  var gFolder = sheet.getRange("outputFolderName").getValues();
  var gSpreadSheetName = sheet.getRange("outputSpreadsheetPrefix").getValues();
  var threadsPerSearch  = sheet.getRange("threadsPerSearch").getValues(); 

  // Number of emails per search:
  var threads = GmailApp.search("-label:" + gLabel, 0, threadsPerSearch); 

  for (var x=0; x<threads.length; x++) {

    var messages = threads[x].getMessages();

    // getting null...a thread without messages is weird
    if(messages != null) {
     for (var y=0; y<messages.length; y++) {

        updateSpreadSheet(messages[y]);

      }
    }

    GmailApp.getUserLabelByName(gLabel).addToThread(threads[x]);
  }
}

I am stuck in the middle of nowhere, have no clue about why this is happening?

Could anyone please guide to resolve the issue?

Answer 1

Problem Solved.

The problem is with string replace function in some other function. I am using the string replace function with regular expression as input to replace function. The regular expression was incorrect due which i am getting the above error.

That's really weird, at least GAS should give some proper error.