Closed Issue: The given key was not present in the dictionary. [2434]

Cause: Too many packages on our custom feed?
Resolution: Archive older packages.

We had ~400 versions for about 10 different packages.

Whenever the Packages folder gets large we get this error:

<error xmlns="http://schemas.microsoft.com/ado/2007/08/dataservices/metadata">
<code/>
<message xml:lang="en-US">An error occurred while processing this request.</message>
<innererror>
<message>The given key was not present in the dictionary.</message>
<type>System.Collections.Generic.KeyNotFoundException</type>
<stacktrace>
at System.Collections.Generic.Dictionary`2.get_Item(TKey key)
at NuGet.Server.Infrastructure.ServerPackageRepository.GetMetadataPackage(IPackage package)
at System.Linq.Enumerable.WhereSelectEnumerableIterator`2.MoveNext()
at System.Linq.Buffer`1..ctor(IEnumerable`1 source)
at System.Linq.OrderedEnumerable`1.<GetEnumerator>d__0.MoveNext()
at System.Linq.Enumerable.<TakeIterator>d__3a`1.MoveNext()
at System.Data.Services.DataService`1.SerializeResponseBody(RequestDescription description, IDataService dataService)
at System.Data.Services.DataService`1.HandleRequest()
</stacktrace>
</innererror>
</error>

Removing everything older than 1 month (getting the count down to about 200 .nupkg files) fixes the solution.
Comments: Seems to be fixed in normally multi-user scenario. Closing it for now. Our load runs would give us more insights.