I Am Relatively new in sharepoint. I have created a small workflow using Visual Studio as a Farm Solution. It works fine for my Server but whem I am trying to deploy it on remote server its disabling the activate option ..it appears to me that i have to deploy it is as a sandbox Solution. I tried by setting the sandbox = true in VS but then its throwing me an error saying "Feature cannot be deployed as Sandbox Solution". Can Any1 Help
You can't deploy farm-level solutions using solutions gallery (it works only for sandbox solutions). However, as you noticed, your workflow could be only farm-level.
So, for adding it you should run PowerShell on remote server and run Add-SPSolution command (cmdlet) in it:
After that you can open SharePoint Central Administration/System settings/Manage farm solutions and you will be able to install your solution and after that you could activate it in Central Administration/System settings/Manage farm features.
If you have further questions, try to google "Add-SPSolution" or ask us questions you have.
PS: If you start google this issue you will see that also you can use stsadm; however, this approach is depreceted and using PowerShell is the recommended way.
PPS: Don't forget to mark as answer/upvote if it helps you :-)