Site creation error

Question

While create a new subsite within a site collection (from the browser),
I get this error:

The url 'Pages/default.aspx' is invalid. it may refer to a nonexistent file or folder or refer to a valid file

I checked the ULS log and the only error I see is this:

System.Data.SqlClient.SqlException (0x80131904): Parameter '@tp_Version' was supplied multiple times. at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection, Action`1 wrapCloseInAction) at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose) at System.Data.SqlClient.TdsParser.TryRun(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj, Boolean& dataReady) at System.Data.SqlClient.SqlDataReader.TryHasMoreRows(Boolean& moreRows) at System.Data.SqlClient.SqlDataReader.TryReadInternal(Boolean setTimeout, Boolean& more) at System.Data.SqlClient.SqlDataRea... dc1f0b9d-a674-f04b-99fb-97d2ef8fc076

Answer 1

Once you use a Design Package to apply a new site branding, beware of removing it from your site as it might cause various issues across the site collection.

Solution 1:

In SharePoint 2013 you cannot uninstall an imported design package, and you should never attempt to deactivate a design package through the solution gallery. If you do, page layout content types are removed and users may not be able to create subsites.

To recover from this state, you should perform the following steps where site A= the original site collection, site B = the site collection with the deactivated design package (bad state), and site C = a new, blank site collection that you have created:

1. Export a design package from site A
2. Import the design package to site C
3. Export a design package from site B
4. Import the design package to site C
5. Export the design package from site C
6. Import the design package to site B

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