Problem after update to latest linux version

Hello,
I just updated my version of manager after a couple of months lag. Everything appeared to proceed exactly as upgrades have in the past. However, when I launched Manager, I received the following message.

17.10.50: SQLite.SQLiteException: ReadOnly
  at SQLite.SQLiteCommand.ExecuteNonQuery () [0x000ae] in <d99df9bc3e8e44e69fa595e0813d407b>:0 
  at SQLite.SQLiteConnection.Execute (System.String query, System.Object[] args) [0x00040] in <d99df9bc3e8e44e69fa595e0813d407b>:0 
  at SQLite.SQLiteConnection.CreateTable (System.Type ty, SQLite.CreateFlags createFlags) [0x0015f] in <d99df9bc3e8e44e69fa595e0813d407b>:0 
  at SQLite.SQLiteConnection.CreateTable[T] (SQLite.CreateFlags createFlags) [0x00000] in <d99df9bc3e8e44e69fa595e0813d407b>:0 
  at Manager.ApplicationData.SQLiteConnection (System.Guid fileId) [0x00056] in <550d92da06db4aca92b06df1c82ef19c>:0 
  at Manager.ApplicationData.Get (System.Guid entityId) [0x00033] in <550d92da06db4aca92b06df1c82ef19c>:0 
  at Manager.Query.Language.GetLanguage (Manager.ApplicationData objects) [0x00006] in <550d92da06db4aca92b06df1c82ef19c>:0 
  at ManagerServer.HttpApplication..ctor (System.String baseDirectory, System.Boolean whitelabel, System.IO.FileInfo fileInfo) [0x0003f] in <80c8f6c62ac4419f9b40c9d03d18c69c>:0 

How do I correct this? Based on the first line, it appears to be some kind of write permission error, but when I search for my database file to check permissions, nothing appears.

I am running Manager on the Desktop with LinuxMint 18.2, and I ran the update manager in Mint before starting the manager update.

Thanks for any help.
Regards,
Greg

you might want to try in the terminal

sudo /usr/bin/mono /usr/share/manager/Manager.exe

I might have the exact paths a bit wrong, but you should be able to work it out by looking at your file system
If Manager runs, then close it, and try and run it as your normal user from the GUI/Menu as normal

Thank you. My install is in the /opt folder.

Bur, launching it from the terminal did the trick. Everything came up and I am now able to use the GUI/menu as before.

I was a little too hasty in responding. I was able to access my business account and some sections appear to be working fine. However when I attempt to access my sales invoices, or my purchase invoices, I receive error messages. (Attached)

When I access my sales quotes, existing quotes appear fine. But when I attempt to create a new quote or change an existing quote, I receive another error message. I’ve attached a screenshot of it as well.

Any thoughts on how to correct this?
Thanks,
Greg

This looks to me to be a permissions problem/issue - - ie more of the same as the problem that you started with

Thanks, That appears to be it. In checking permissions, the database owner was set to root. When I changed it to the correct user, everything cleared up. Not sure how or why the owner/permissions changed after the upgrade.