Could not load file or assembly 'log4net, Version=1.2.10.0, Culture=neutral, PublicKeyToken=692fbea5521e1304' or one of its dependencie

LOG: DisplayName = log4net, Version=1.2.10.0, Culture=neutral, PublicKeyToken=692fbea5521e1304
 (Fully-specified)
LOG: Appbase = file:///C:/inetpub/wwwroot/source/photos/
LOG: Initial PrivatePath = C:\inetpub\wwwroot\source\photos\bin
Calling assembly : SaleWeb, Version=1.0.0.2, Culture=neutral, PublicKeyToken=null.
===
LOG: This bind starts in default load context.
LOG: Using application configuration file: C:\inetpub\wwwroot\source\photos\web.config
LOG: Using host configuration file: C:\Windows\Microsoft.NET\Framework\v4.0.30319\aspnet.config
LOG: Using machine configuration file from C:\Windows\Microsoft.NET\Framework\v4.0.30319\config\machine.config.
LOG: Post-policy reference: log4net, Version=1.2.10.0, Culture=neutral, PublicKeyToken=692fbea5521e1304
LOG: Attempting download of new URL file:///C:/Windows/Microsoft.NET/Framework/v4.0.30319/Temporary ASP.NET Files/root/d32568ff/abb1a9ab/log4net.DLL.
LOG: Attempting download of new URL file:///C:/Windows/Microsoft.NET/Framework/v4.0.30319/Temporary ASP.NET Files/root/d32568ff/abb1a9ab/log4net/log4net.DLL.
LOG: Attempting download of new URL file:///C:/inetpub/wwwroot/source/photos/bin/log4net.DLL.
WRN: Comparing the assembly name resulted in the mismatch: Build Number
ERR: Failed to complete setup of assembly (hr = 0x80131040). Probing terminated.