We ran into this extremly weird bug today.
Steps to reproduce:
(0.) Have a sharepoint site available where you can export things from excel. Any site will do.
- Write Some stuff in Excel, like
klas von klas 1
Jan 2
ta fram af 3
Ulf 4
(this would be 8 cells spanning A1 to b4)
Select the entered values and choose Insert (I think, It is called infoga in swedish) and then Table in the ribbon.
Mark any cell in the table and choose Design (Table tools) and Export to a Sharepoint List. (You don't actually have to click the final ok button, so nothing will be exported in this test)
Write the url of a sharepoint site and a name for the table. Click next. Now, Excel may or may not tell you that one of the columns are of type Text(Multiple rows). And if so, the column "Key cell(?)" (Nyckelcell) will tell you the first cell in A1 ... An that excel thinks is a multiple line text.
Here are some cell values that my project manager used that triggered the bug:
We have tried these words on multiple client computers and multiple sharepoint sites, and we can reproduce the error everywhere. We are using a swedish language version of Excel 2010 if it matters.
"ta fram af" seems pretty innocent, but SQL Backup made me wonder if it was some kind of internal encoding to prevent injection attacks. It appears "Drop Table" is also considered multiple lines. But that may have been just a coincidence because I tried lots of other injection smelling lines, and they went through.
To give you some background on why this multiple line business is important: When a table is exported to sharepoint like this, the first column consisting only of single line text becomes the "Title" field and gets the ECB menu in sharepoint. If one of the lines is marked as multiple lines, Excel will move on to the next column and the resulting list in SharePoint will have the wrong title column, or no title column at all.
edit: Yes, I now realise that this should have been an "improve the question" post and not an answer post.
edit 2011-12-29: Kit Menke (below), I believe this is the exact same problem as the original poster had. When exporting excel data to SharePoint, Excel treats some cells as multiple lines of text in an arbitrary, but deterministic way. Most sentances are treated as single line of text, but some magic words are treated as multiple lines of text. My post includes a step by step guide to recreate the bug. The bug is so random and weird that I think you have to see it to believe it. It is not a user error, but an actual bug in Excel.