Oh that's annoying! Not sure what happened, but it might be a permissions problem.

If you could have a look in the windows event log for the exception, that would be good to help debug.

Hi again

I really don't have that option since it's not running on a local machine.  And I don't have access to the windows event log where the site is hosted.
Do you know if there is any logging within Umbraco I can take a peek in ?

More info.
Apparently it doesn't happen on all images. Both images are taken with the same camera and downloaded from flickr.

This one works like a charm: http://dammark.dk.nt12.unoeuro.com/media/415/3827486822_acc13cf549_o.jpg
This one falis: http://dammark.dk.nt12.unoeuro.com/media/107/4978735357_669797a58f_b.jpg

And then I found this in the UmbracoLog table in the database.

ID USERID NODEID DATESTAMP LOGHEADER LOGCOMMENT
1731 0 -1 2010-11-22 11:14:01 Error [UmbracoExamine] Cannot index queue items, another indexing operation is currently in progress,

ID USERID NODEID DATESTAMP LOGHEADER LOGCOMMENT

1732 0 -1 2010-11-22 11:14:03 Error At /umbraco/editMedia.aspx?id=1068 (Referred by: http://dammark.dk.nt12.unoeuro.com/umbraco/editMedia.aspx?id=1068): System.NullReferenceException: Object reference not set to an instance of an object.

at Cultiv.MetaDataHandler.CreateMetaData.CreateMediaMetaData(Media sender, SaveEventArgs e)
at umbraco.cms.businesslogic.media.Media.SaveEventHandler.Invoke(Media sender, SaveEventArgs e)
at umbraco.cms.businesslogic.media.Media.FireAfterSave(SaveEventArgs e)
at umbraco.cms.businesslogic.media.Media.Save()
at umbraco.cms.presentation.editMedia.Save(Object sender, EventArgs e)
at System.EventHandler.Invoke(Object sender, EventArgs e)
at umbraco.controls.ContentControl.saveClick(Object Sender, ImageClickEventArgs e)
at System.Web.UI.WebControls.ImageButton.OnClick(ImageClickEventArgs e)
at System.Web.UI.WebControls.ImageButton.RaisePostBackEvent(String eventArgument)
at System.Web.UI.WebControls.ImageButton.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument)
at System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument)
at System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData)
at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)

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