I'm getting this one too on 1.26. Linux 64bit. Have tried reinstalling, removing Modularfueltanks, reinstalling and starting a new career. Anyone got any ideas? My version of the error: UriFormatException: URI scheme must start with a letter and must consist of one of alphabet, digits, '+', '-' or '.' character. at System.Uri.Parse (UriKind kind, System.String uriString) [0x00000] in <filename unknown>:0 at System.Uri.ParseUri (UriKind kind) [0x00000] in <filename unknown>:0 at System.Uri..ctor (System.String uriString, Boolean dontEscape) [0x00000] in <filename unknown>:0 at System.Uri..ctor (System.String uriString) [0x00000] in <filename unknown>:0 at TweakScale.PathEx.MakeRelativePath (System.String fromPath, System.String toPath) [0x00000] in <filename unknown>:0 at TweakScale.Tools.KSPRelativePath (System.String path) [0x00000] in <filename unknown>:0 at TweakScale.Tools.Logf (System.String format, System.Object[] args) [0x00000] in <filename unknown>:0 at TweakScale.TweakScaleUpdater+<createUpdaters>d__0.MoveNext () [0x00000] in <filename unknown>:0 at System.Collections.Generic.List`1[TweakScale.IRescalable].AddEnumerable (IEnumerable`1 enumerable) [0x00000] in <filename unknown>:0 at System.Collections.Generic.List`1[TweakScale.IRescalable]..ctor (IEnumerable`1 collection) [0x00000] in <filename unknown>:0 at System.Linq.Enumerable.ToArray[IRescalable] (IEnumerable`1 source) [0x00000] in <filename unknown>:0 at TweakScale.TweakScale.Setup () [0x00000] in <filename unknown>:0 at TweakScale.TweakScale.OnStart (StartState state) [0x00000] in <filename unknown>:0 at Part.ModulesOnStart () [0x00000] in <filename unknown>:0 at Part+^R^F.MoveNext () [0x00000] in <filename unknown>:0