Hello Guys. I am currently doing an ASP.Net project.. I need to do postback on a page as after I have chosen a value from a dropdownlist, I need to update it to a text field on the same page as well. As there are quite a number of records in the dropdownlist, I received an error stating "The viewstate is invalid or page is corrupted". Is it because that the viewstate size is not big enough? If that is the case, what should I do to allow the page to work correctly. Please help. Thanks a lot.

How large is the list ?

Actually it depends. One was around 2000 items in the list. And immediately after postback, the error came out. Another was around 200 over items in the list. And after a few postback, the same problem came out as well. However the strange thing is that, I tried on different PCs and some got this problem while some don't. That is why I am wondering why I get this error.

Where is the list being generated from ? How long does it take to load the initial list ? 2000 items brings up other issues as well...

Actually I retrieve records from a table in a database (either MS Access or SQL Server), then I bind it to the dropdownlist. It took me around 5 to 10 seconds to load up the entire page, including the initial list.

Some other issues? Please advice. I am pretty poor in ASP.net and its behaviour. Thanks a lot.

How many concurrent users will you have on this web server ?

mmm... There could be as many as 10 to 15 users logging in at one time..

Have you tried enabling trace functionality for this page and watch the performance/viewstate information ?

I am curious to see the results of the trace when are able to submit the page a few time before it fails.