diff --git a/fpga/lib/card.cpp b/fpga/lib/card.cpp
index 1048b41b4..2428fe5d5 100644
--- a/fpga/lib/card.cpp
+++ b/fpga/lib/card.cpp
@@ -69,9 +69,10 @@ std::shared_ptr<ip::Core> Card::lookupIp(const ip::IpIdentifier &id) const {
 bool Card::unmapMemoryBlock(const MemoryBlock &block) {
   if (memoryBlocksMapped.find(block.getAddrSpaceId()) ==
       memoryBlocksMapped.end()) {
-    throw std::runtime_error(
+    logger->warn(
         "Block " + std::to_string(block.getAddrSpaceId()) +
         " is not mapped but was requested to be unmapped.");
+        return false;
   }
 
   auto &mm = MemoryManager::get();