Just got an error first time loading:
Ionic.Zip.ZipException: Cannot read that as a ZipFile ---> Ionic.Zip.BadReadException: Bad signature (0x21726152) at position 0x00000000
at Ionic.Zip.ZipEntry.ReadHeader(ZipEntry ze, Encoding defaultEncoding)
at Ionic.Zip.ZipEntry.ReadEntry(ZipContainer zc, Boolean first)
at Ionic.Zip.ZipFile.ReadIntoInstance_Orig(ZipFile zf)
at Ionic.Zip.ZipFile.ReadIntoInstance(ZipFile zf)
--- End of inner exception stack trace ---
at Ionic.Zip.ZipFile.ReadIntoInstance(ZipFile zf)
at Ionic.Zip.ZipFile.Read(Stream zipStream, TextWriter statusMessageWriter, Encoding encoding, EventHandler`1 readProgress)
at Terraria.TexturePackSupport.FindTexturePacks()
at Terraria.Main.LoadContent()
at Microsoft.Xna.Framework.Game.Initialize()
at Terraria.Main.ClientInitialize()
at Terraria.Main.Initialize()
at Microsoft.Xna.Framework.Game.RunGame(Boolean useBlockingRun)
at Terraria.Program.LaunchGame(String[] args, Boolean monoArgs)