Unable locate installable unit in target definition

Question

I created my own target definition. It worked perfectly until now. Today I opened this target definition and got following error for all software sites I have there:

Unable to locate installable unit <unit name>

The target definition file looks like this:

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<?pde version="3.6"?>

<target name="indigo" sequenceNumber="20">
<locations>
<location includeAllPlatforms="false" includeMode="planner" includeSource="true" type="InstallableUnit">
<unit id="org.eclipse.zest.feature.group" version="1.3.0.v20110425-2050-67A18yF6F18CBD5A7N54242"/>
<unit id="org.eclipse.zest.sdk.feature.group" version="1.3.0.v20110425-2050-67C18COMPIAKSVKGQaRTQTiSN8WP"/>
<unit id="org.eclipse.zest.source.feature.group" version="1.3.0.v20110425-2050-67A18yF6F18CBD5A7N54242"/>
<repository location="http://download.eclipse.org/releases/indigo"/>
</location>
<location includeAllPlatforms="false" includeMode="planner" includeSource="true" type="InstallableUnit">
<unit id="org.eclipse.jdt.feature.group" version="3.7.2.v20120120-1414-7z8gFcuFMP7BW5XTz0jLTnz0l9B1"/>
<unit id="org.eclipse.jdt.source.feature.group" version="3.7.2.v20120120-1414-7z8gFcuFMP7BW5XTz0jLTnz0l9B1"/>
<unit id="org.eclipse.pde.source.feature.group" version="3.7.2.v20120120-1420-7b7rFUOFEx2Xnqafnpz0E--0"/>
<unit id="org.eclipse.platform.sdk" version="3.7.2.M20120208-0800"/>
<unit id="org.eclipse.rcp.id" version="3.7.2.M20120208-0800"/>
<unit id="org.eclipse.rcp.sdk.id" version="3.7.2.M20120208-0800"/>
<repository location="http://download.eclipse.org/eclipse/updates/3.7"/>
</location>
<location includeAllPlatforms="false" includeMode="planner" includeSource="true" type="InstallableUnit">
<unit id="org.eclipse.egit.feature.group" version="1.3.0.201202151440-r"/>
<unit id="org.eclipse.egit.source.feature.group" version="1.3.0.201202151440-r"/>
<unit id="org.eclipse.jgit.feature.group" version="1.3.0.201202151440-r"/>
<unit id="org.eclipse.jgit.source.feature.group" version="1.3.0.201202151440-r"/>
<repository location="http://download.eclipse.org/egit/updates"/>
</location>
<location path="${project_loc}/lib" type="Directory"/>
<location includeAllPlatforms="false" includeMode="planner" includeSource="true" type="InstallableUnit">
<unit id="org.tmatesoft.svnkit.feature.group" version="1.7.4.t20120412_2022"/>
<repository location="http://eclipse.svnkit.com/1.7.x"/>
</location>
<location path="${project_loc}/lib/deltapack" type="Profile"/>
</locations>
</target>

Answer 1

This is a known issue with Eclipse, and unfortunately, there is no clear solution. Things that may fix this:

• Restart Eclipse
• Select all entries and hit "Reload"
• Restart Eclipse with the -clean command line option (no worries, does not erase workspace)
• Select an entry and open it (hit "Add..."). The old selection will be lost, so you have to reselect it. Upon closing, the target platform will be reloaded, and with a little luck everything, not just the update site that you just edited.
• The nuclear option: Delete the .metadata folder in your workspace - you'll have to setup your workspace again.

Answer 2

For me editing the .target file manually and increasing the sequenceNumber attribute worked every time (so far).