w-form.dll is a process that belongs to the w-sign: IT Solution Signature DLL program, which is made by IT Solution GmbH. IT Solution GmbH is a German partner for Microsoft. They offer products and applications that you may be running on your computer. If there was a new program or application installed or deleted, an error may have occurred during the process. This happens sometimes and is fairly common.
In order to get your computer back on track, you should invest in a reputable registry cleaner such as ZookaWare PC Cleaner. ZookaWare PC Cleaner can clear errors usually with the first scan. If not possible, then they guarantee a solution within the first 24 hours.
ZookaWare PC Cleaner also offers a money back guarantee if you are not completely satisfied. Only a company fully confident in its ability to deliver on its promise would offer such a guarantee.