>>Hi all,
>>
>>Suddenly few of the forms when open, produced the above error message.What
>>causes the above?
>>
>>Thanks.
>
>Farouk. This error is normally asscociated with corrupted index files. Does your form use a data environment? If so then perhaps a table in the DE has a corrupted index. Try and find the table and pack/reindex that.

Thanks Jos for the tip. I have found out 1 of my form class corrupted. Restoring the backup class resolve the issue.

Regards.