HTTP500 error LoadRunner Oracle NCA script

I have recorded a script from login till the opening of Oracle form. Then i split the program into two parts, one with login and other as Navigation to form and open.

Login is successfully executing but the navigation script is giving me an error HTTP-error code 500

T03_Amar_Navigation.c(95): Error -26612: HTTP Status-Code=500 (Internal Server Error) for the URL [MsgId: MERR-26612].

there is no problem while logging in and opening oracle form manually.

can someone help me what I may be missing?

I tried copying all the correlation parameters into the navigation as well, no error or mismatch with correlation parameters

Best guess, based upon seeing this 500 condition hundreds of times in my career, is that you need to check your script for the following

• Explicit checking for success on each step, or expected results. This is more than just accepting an HTTP 200. This involves actually processing the content that is returned and objectively looking at the page for elements you expect to be present. If they are not present then you will want to branch your code and elegantly exit your iteration. A majority of 500 level events are simply the result of poor testing practices and not checking for expected results.
• Very carefully examine your code for unhandled dynamic elements. These could be related to session, state, time or a variable related to user/business process. A mishandled or unhandled dynamic element cascading for just a few pages results in an an application where the data being submitted does match the actual state of the business process. As this condition is something that would not be possible with the actual website, you wind up with an unaddressed exception in the code and a 500 pushed back to the user. There are roughly half a dozen methods for examining your requests for dynamic elements. I find the most powerful to be the oldest, simply record the application twice for the same data, then compare the scripts. Once you have addressed the items related to session, state and time, then record with a different data set (user, account, etc...) and look at the dynamic elements related to your actual data in use.

Address the two items above and your 500 will quite likely go away.