I am a little unsure of your 'difficulties' and it is not possible for us to give you a "Go-Ahead" without knowing the background of why you had to stop migration.
This link helps you through the migration process of PF.
This link is a great overview read of the entire process as well as more steps to follow if it is easier for you to follow this process.
Yes, you can resume your public folder migration by using
Resume-PublicFolderMigrationRequest
Moreover, Please refer to the following article to migrate public folders from Exchange 2007 to Exchange 2013.
Migrate Public Folders to Exchange 2013 From Previous Versions:
https://technet.microsoft.com/en-us/library/jj150486.aspx?f=255&MSPPError=-2147217396
If the above posted solution didn't work for you then If you wish you may try this application i.e.
http://www.lepide.com/exchangemigrator/public-folder-migration.html that allows you to schedule your migration job as per your requirement and lets you to migrate Public Folder
content swiftly from Exchange 2007 to Exchange 2013.
Hope it helps you!
- Edited by vincentburton 18 hours 29 minutes ago
Yes, you can resume your public folder migration by using
Resume-PublicFolderMigrationRequest
Moreover, Please refer to the following article to migrate public folders from Exchange 2007 to Exchange 2013.
Migrate Public Folders to Exchange 2013 From Previous Versions:
https://technet.microsoft.com/en-us/library/jj150486.aspx?f=255&MSPPError=-2147217396
If the above posted solution didn't work for you then If you wish you may try this application i.e.
http://www.lepide.com/exchangemigrator/public-folder-migration.html that allows you to schedule your migration job as per your requirement and lets you to migrate Public Folder
content swiftly from Exchange 2007 to Exchange 2013.
Hope it helps you!
- Edited by vincentburton Tuesday, August 04, 2015 12:56 PM
Hi,
You can use the Suspend-PublicFolderMigrationRequest cmdlet to suspend a migration request any time after the request was created, but before it reaches the status of CompletionInProgress. You can resume the migration request by using the Resume-PublicFolderMigrationRequest cmdlet.
In addition, I have found the below article about migration from Ex2007 to Ex2013, I suggest you can follow the guide to complete the migration.
Regards,
David