tag:blogger.com,1999:blog-7960725789043363799.post3920082166568358644..comments2023-12-14T23:28:20.080-08:00Comments on CSharp Techies: Invalid postback or callback argument on Post backSaifhttp://www.blogger.com/profile/03928635339145093205noreply@blogger.comBlogger1125tag:blogger.com,1999:blog-7960725789043363799.post-29495087652908414452012-07-01T14:50:19.130-07:002012-07-01T14:50:19.130-07:00I have to tell you that I was about to pull my hai...I have to tell you that I was about to pull my hair out until I found this post. I have an updatepanel inside an iframe with a dropdownlist of addresses. The iframe is for sending a text message and my address object had "\r" in the dropdown value as an attempt at newlines in the sent text message. I had tried everything from registering the control for validation in the render method to switching to a regular select element. This worked for me, thanks so much!Anonymousnoreply@blogger.com