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            <b><a class="bz_bug_link 
          bz_status_RESOLVED  bz_closed"
   title="RESOLVED WONTFIX - "images to stack" does not work"
   href="http://fiji.sc/bugzilla/show_bug.cgi?id=1000#c8">Comment # 8</a>
              on <a class="bz_bug_link 
          bz_status_RESOLVED  bz_closed"
   title="RESOLVED WONTFIX - "images to stack" does not work"
   href="http://fiji.sc/bugzilla/show_bug.cgi?id=1000">bug 1000</a>
              from <span class="vcard"><a class="email" href="mailto:ctrueden@wisc.edu" title="Curtis Rueden <ctrueden@wisc.edu>"> <span class="fn">Curtis Rueden</span></a>
</span></b>
        <pre>Thanks Wayne!

Here is a patch that tells the user this when such a circumstance occurs:

diff --git a/src/main/java/ij/plugin/ImagesToStack.java
b/src/main/java/ij/plugin/ImagesToStack.java
index e84d924..d72dc30 100644
--- a/src/main/java/ij/plugin/ImagesToStack.java
+++ b/src/main/java/ij/plugin/ImagesToStack.java
@@ -38,15 +38,22 @@ public class ImagesToStack implements PlugIn {
                        return;
                }

-               int count = 0;
+               int count = 0, stackCount = 0;
                image = new ImagePlus[wList.length];
                for (int i=0; i<wList.length; i++) {
                        ImagePlus imp = WindowManager.getImage(wList[i]);
                        if (imp.getStackSize()==1)
                                image[count++] = imp;
+                       else
+                               stackCount++;
                }
                if (count<2) {
-                       IJ.error("Images to Stack", "There must be at least two
open images.");
+                       if (stackCount >= 2) {
+                               IJ.error("Images to Stack", "The \"Images to
Stack\" command " +
+                                       "does not work with stacks as
input.\nInstead, use the " +
+                                       "Image>Stacks>Tools>Concatenate
command.");
+                       }
+                       else IJ.error("Images to Stack", "There must be at
least two open images.");
                        return;
                }</pre>
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