runtime error 402: in vb 6.0

Im facing a runtime error 402
Can any 1 plz help me y this error occurs.

What is the error description and what exactly are you doing that causes the error?

"Code must close topmost modal form first "
This is the error message im rcving...This error does not occur every time but some times when i use to open a modal form it shows the error and when i close the mesage box application also got closed...plz help me i could not b able t5o trace it out...

see this link http://msdn.microsoft.com/library/de...ottopmodal.asp

the content is

Must close or hide topmost modal form first (Error 402)
Specifics

The modal form you are trying to close or hide isn't on top of the z-order. This error has the following cause and solution:

Another modal form is higher in the z-order than the modal form you tried to close or hide.
First use either the Unload statement or the Hide method on any modal form higher in the z-order. A modal form is a form displayed by the Show method, with the style argument set to 1 vbModal.

thnx ganeesh...
actually sequence of my application is as follows:
first I save a record of a student ... before saving the record student's elegibility is checked ... this eligibility is being checked on a modal form...after checking(unloading) of eligibility modal form my record got saved...after saving record on main form then i need to enter some comments...for which i click on a button which opens a modal form...most of the time no error occur on opening of this second modal form but rarely this run time error occurs...:(

Thnx Ganees ... with ur reply i hav bcome able to trace out the root cause of this problem.. noe I think i could handle it in some appropriate way ... Well thanx alot u have been very helpful to me :)

noshaba: you are most welcome